## The International Research Center

### Seminars

15.05.2019 12:00
PhD student

Metasurfaces for high transparency and full absorption
Abstract: We present a novel optical effect where the scattered light on dielectric particles is suppressed simultaneously in the forward and backward directions. In contrary to the quadrupolar generalized Kerker conditions, this effect requires the coherent dipoles to be in π phase with their quadrupole counterparts. Electric dipole Fano profile and quadrupoles long-wavelength characteristics together set the physical environment to satisfy these conditions at a certain spectral position. The metasurface constructed from transverse scatterers is extraordinarily transparent for the incident light where neither the phase nor the amplitude is perturbed. We then demonstrate a mechanism of full absorption from dielectric metasurfaces deposited on a conducting sheet.
You are very welcome to attend! ​

515 room​​ (Birzhevaya line, 14-16​)

10.04.2019 12:00
Анна Николаева

Направленное испускание фотонов в процессе спонтанного параметрического рассеяния резонансной наночастицей
Abstract: Работа посвящена исследованию спонтанного параметрического рассеяния резонансной диэлектрической наночастицей, обладающей ненулевым тензором нелинейной восприимчивости χ (2). С помощью аппарата двухфотонной амплитуды рассмотрены пространственные корреляции между фотонами, генерируемыми при возбуждении низших дипольных Ми-резонансов. В работе получены условия направленного испускания фотонов при коллинеарном распаде, а также для распада в противоположных направлениях. Этот эффект можно рассматривать как аналог эффекта Керкера, но для квантово-коррелированных фотонов. ​

515 room​​ (Birzhevaya line, 14-16​)

10.04.2019 12:00

Spatially uniform states and dissipative solitons in the systems supporting bound state in the continuum
Abstract: In the present talk, I will discuss nonlinear dynamics of the driven-dissipative system with symmetry protected bound state in the continuum. The considered system is a periodically grated one-dimensional optical waveguide with Kerr nonlinearity. We analyzed in details spatially uniform states and their stability and also showed that in such system change of nonlinearity sign alters the properties of the homogeneous states drastically. We demonstrated that several types of localized nonlinear states – such as bright, dark solitons and domain walls - can form on the stable spatially uniform backgrounds. We calculated the bifurcation diagrams and stability properties of the solitons and showed that the solitons can form on the backgrounds of different symmetries. We found Maxwell’s points of the domain walls. Also, we studied interaction properties of different types of solitons. After providing the analysis of solitons, we suggested and discussed a finite system with varying parameters where the solitons can be observed experimentally. ​

515 room​​ (Birzhevaya line, 14-16​)

27.03.2019 12:00
Иван Врубель
Доклад по материалам кандидатской диссертации

Влияние точечных дефектов на электронную структуру и процессы переноса заряда в смешанных (Y,Lu,Gd)3(Al,Ga)5O12 гранатах
Abstract: Ключевым элементом медицинской техники, основанной на регистрации ионизирующих излучений, является сенсор — сцинтиллятор. Сцинтиллятор — это материал, конвертирующий поток ионизирующего излучения в оптический сигнал, предназначенный для регистрации обычными оптическими приемниками. Современный уровень развития фотоприемников, электроники и компьютерных систем приводит к тому, что сцинтиллятор в настоящее время является ограничивающим элементом таких установок, как компьютерные (CT) и позитрон-эмиссионные (PET) томографы. Работа посвящена исследованию, характеризации и развитию сцинтилляционных керамик на базе кристаллической структуры граната, легированного активатором Ce3+. С помощью квантово-механического моделирования изучены эффекты, возникающие при создании твердых растворов многокомпонентных гранатов (bandgap engineering). Идентифицированы и охарактеризованы электронные ловушки, связанные с ионами Yb3+ и Eu3+, определена их роль в зарядовом транспорте. Определены типы и концентрации примесей, участвующих в формировании кинетики люминесценции, рассчитаны сечения центров захвата Ce4+ и Yb3+. Дано микроскопическое описание кинетики люминесценции. ​

515 room​​ (Birzhevaya line, 14-16​)

20.02.2019 12:30
Nikita Olekhno​
ITMO University

Topological states of interacting photons realized with an electrical circuit
Abstract: In the present talk, I will discuss a chain of optical microresonators with tunneling couplings between them described by the extended Bose-Hubbard model. We focus on photon pairs traveling in the array and interacting with each other in a repulsive manner due to inherent nonlinearity of the resonators when direct two-photon tunneling is enabled. In the considered model photons can form bound pairs (doublons). We show that such one-dimensional two-particle quantum problem allows for exact mapping onto the two-dimensional electrical circuit, described by classical Kirchhoff's rules. Resonances in the obtained circuit consisting of inductors and capacitors correspond to the excitations of the initial one-dimensional two-particle model. We report the experimental realization of such setup providing the signatures of delocalized doublons as well as a topological edge state of bound photon pairs. Besides the spectral positions of doublon modes, we also extract the topological invariant directly from the measurements and perform the eigenmode reconstruction. Our measurements prove the existence of the topological doublon edge state which persists despite the disorder present in the system. ​

301/5 room​​ (Birzhevaya line, 14​)

13.02.2019 12:00
Oleh Yermakov
ITMO University

Broadband polarization degeneracy of guided modes in photonic crystal waveguide and its applications.
Abstract: The dispersion of electromagnetic waves in a free space is double degenerate with respect to polarization for all frequencies and propagation directions. It is well-known and fundamental operational principle for any polarization device. However, surface and guided waves spectra are typically either not degenerate at all or meet degeneracy only at very specific dispersion points. It significantly limits the development of flat optics devices. In this work, we demonstrate the broadband TE and TM guided mode degeneracy with the periodic subwavelength pattern of dielectric cylinders. We show that the degeneracy can be achieved via tuning the period of the structure and the cylinder aspect ratio, and evaluate the degeneracy degree. These results can be conveniently scaled to any frequency range in the near-IR following the rules adopted for photonic crystals. Finally, we propose the conceptually new practical application based on the guided modes degeneracy, namely linear-to-circular ‘waveguide polarizer’. The devices proposed exhibit great opportunities for the integrated circuits, on-chip and flat optics devices using the polarization degree of freedom of localized waves for the optical encoding, transfer and processing information. ​

2503 room​​ (Lomonosova,9​​​)

06.02.2019 11:40
Dr. Maxim Yurkin
Voevodsky Institute of Chemical Kinetics and Combustion (ICKC), Novosibirsk, Russia

The discrete dipole approximation for electromagnetic simulations
Abstract: Light scattering is widely used in remote sensing of various objects ranging from metal nanoparticles and macromolecules to atmospheric aerosols and interstellar dust, being in some cases the only available approach to characterize their geometric or optical properties. Moreover, the structure of electromagnetic fields near a particle is also of major importance for other phenomena, such as surface-enhanced Raman scattering or electron energy-loss spectroscopy. All these applications require accurate simulations of interaction of electromagnetic fields with particles, which is not trivial for particles of arbitrary shape and internal structure with sizes comparable to or larger than the wavelength.

The discrete dipole approximation (DDA) is one of the general methods to handle such problems. In this talk I will provide an introduction to the DDA, including both the basic underlying physical picture and rigorous derivation starting from the integral form of Maxwell’s equation for the electric field. The latter shows that the DDA is a numerically exact method and a special case of volume-discretization method of moments. Apart from the standard problem of far-field scattering by single isolated particles, the DDA can also be applied to particles in complicated environments (e.g. on substrate) and to other electromagnetic physical phenomena. I will also discuss computational aspects, including the latest efficiency improvements, and briefly review the existing open-source DDA codes, which made the method so popular in the light-scattering community. ​

2432 room​​ (Lomonosova,9​​​)

29.01.2019 12:00
Yuri Krivosenko
ITMO University

Resonant edge-site pumping of Su-Schrieffer-Heeger lattices
Abstract: Su-Schrieffer-Heeger chains modelled as optical lattices (OL) loaded with exciton-polaritons have been theoretically investigated. The relative phases of the lasers constructing the OL have controlled the topological state, the hopping amplitudes have been calculated within the harmonic approximation to the optical potential in the vicinity of its minima. The chains have been subject to the resonant pumping of the edge site and shaken in either adiabatic or high-frequency regime. The dynamic problem of the occupation of the lattice sites and eigen states has been semianalytically solved. Finally, the analysis of the evolution of the occupation numbers has disclosed that gapless, topologically trivial and non-trivial chain configurations manifest different qualitative and quantitative behaviour.​ ​

301/5 room​​ (Birzhevaya line, 14​)

23.01.2019 12:00
Ivan Toftul
ITMO University

Orbital and spin angular momenta of circular waveguide modes and related optomechanical effects on nanoparticles
Abstract: This seminar reports on the results obtained during a six months visit to Okinawa Institute of Science and Technology, the unit led by Prof. Sile Nic Chormaic. We start by presenting a comparison between the modes of a sphere and a circular waveguide. The circular dielectric waveguides have a wide range of applications in physics starting from optical communications and biomedicine, to fundamentals of light-matter interaction. We apply a novel approach [Bliokh, Konstantin Y., Aleksandr Y. Bekshaev, and Franco Nori. PRL 119.7 (2017): 073901] for the calculation of the angular momentum of the circular waveguide modes and discuss their quantization mechanism. Using this approach spin and orbital parts of light angular momentum are clearly separated. In the second part, we provide the connection between the linear and angular momentum of the waveguiding modes and mechanical quantities such as optical pressure and torque. We consider the mechanical action of the evanescent field of cylinder modes on nanoparticles in the dipole approximation and beyond. We discuss the optomechanical effects related to surface-induced anisotropy in small nanoparticles and demonstrate the non-trivial behaviour of the arbitrarily sized particles using a generalized Mie theory.​ ​

Lomonosova,9​​, room 1223

27.12.2018 11:00
Sergei Koniakhin
Institut Pascal, PHOTON-N2, Universite Clermont Auvergne, CNRS, France

Complex behavior of topological defects in polaritonic BECs
Abstract: Exciton-polariton system in semiconductor heterostructures have unique properties due to the combination of optical generation possibility and strong nonlinear interaction, stemming from the exciton component. The latter originates such complex topological condensate excitations as quantum vortices and solitons. The first part of the talk is devoted to quantum turbulence. The coexistence of the energy and enstrophy cascades in 2D quantum turbulence is one of the important open questions in the studies of quantum fluids. We will show that polariton condensates are particularly suitable for the possible observation of scaling on sufficiently large scales. The shape of raw energy spectra depends on the procedure of condensate excitation (stirring) but the energy spectra of clustered vortices always exhibit the -5/3 power law. In the optimal case, the cascade can be observed over almost 2 decades. In the second part of the talk we will theoretically elucidate the available experimental data on the solitons propagation and stability in the resonantly driven cavity in the pump/support scheme. Inspired by this phenomenon we will study the soliton propagation in the all-optically patterned maze and demonstrate the essential feature of maze solving. Finally we will demonstrate the concept of all-optically controlled soliton switch/transistor. ​

301/5 room​​ (Birzhevaya line, 14​)

19.12.2018 12:00
Mikhail Lapine
Associate Professor, University of Technology Sydney, Sydney, Australia

New degrees of freedom in metamaterial research
Abstract: The extravagant field of metamaterials has been shining with bright ideas and promising designs for more than a decade of an impressive progress. While metamaterials are now seeking their way towards applications, the basic ideas for their assembly are far from being exhausted. One of the major highlights of metamaterials is their emergent properties which were not available with the building blocks alone. This is achieved through a collective response of carefully designed elements (“meta-atoms”), arranged so that their individual features mix with their mutual interaction to yield unusual macroscopic properties. I will review a set of selected highlights regarding the design of conceptually novel implementations, targeted to combine and interlink electromagnetic, acoustic or even thermal properties, resulting in magnetoelastic, conformational or optomechanical nonlinearities. The tricks we used to achieve such interactions, rely on a hybrid structure, where the building blocks of metamaterials include elements with quite different functionality, being arranged in a special way to impose a direct interaction between very distinct properties. I will discuss the past, present, and future of the advanced features of metamaterial designs, which are made possible by tweaking their structural peculiarities, and present several examples of how hybrid designs will bring new phenomena into play, and lead to curious multi-physics of metamaterial response. ​

301/5 room​​ (Birzhevaya line, 14​)

19.12.2018 12:00
Alexander Solntsev
Senior Researcher, University of Technology Sydney, Sydney, Australia

Quantum optics on a nonlinear chip
Abstract: Quantum entanglement is a special connection between the particles, which enables correlations without interaction. Entangling photons, elementary particles of light, brings the promise of secure communication and ultra-fast quantum computing. Another phenomenon called optical nonlinearity allows interaction between electro-magnetic waves of different colors. Bringing the concepts of quantum entanglement and optical nonlinearity together, and integrating them on a chip, opens a way to efficiently generate entangled photons and tune the entanglement.​ ​

301/5 room​​ (Birzhevaya line, 14​)

17.12.2018 10:00

Research projects of younf scientists of the center for Nanophotonics and Metamaterials

14.12.2018 11:00
Anvar Zakhidov
University of Texas at Dallas

BMRI and what can be done jointly for collaborating with Aurora research team.
Abstract: Aurora company in Boston has developed highly sensitive and specialized MRI, which is 1.5 tesla system with AI: artificial intelligence data analysis. Aurora is based in Danvers, Massachusetts, is the leading corporation committed to fight against breast cancer through advanced technology in imaging and data science. Since 2009, Aurora has successfully rolled out the dedicated breast MRI mobile service in the United States, and soon will be in China as well (seminar within the framework of the scientific-educational workshop"New dielectric materials for practical radiophysics").

14.12.2018 10:00
Alexey Kimel
Radboud University, Nijmegen, The Netherlands, МТУ МИРЭА, Москва, Россия

Femtosecond opto-magnetism: from fundamentasl to ultrafast data recording
Abstract: The action of electric field of light on electronic dipoles, being the largest perturbation in physics of light-matter interaction, conserves the spin of electron. Nevertheless, an effective optical control of spins and spin-polarized currents become possible due to effects of light on the spin-orbit and the exchange interactions. Here I will review the fundamentals and the recent progress in the areas of femtosecond opto-magnetism and opto-spintronics. It will be shown that femtosecond circularly polarized laser excitation can switch magnetization of media in a controllable way such that the direction of switching is fully determined by the polarization of light. We will also demonstrate optical generation and control of spin-polarized electric currents and THz magnons at the femtosecond timescale. It will be argued that femtosecond laser pulses open up new opportunities for recording and processing of magnetic information. ​

301/5 room​​ (Birzhevaya line, 14​)

10.12.2018 22:37

Scientific and educational workshop new dielectric materials for practical radiophysics
Abstract: Program

27.11.2018 11:00
Guoxiang Huang
State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, China
NYU-ECNU Joint Institute of Physics at NYU-Shanghai, Shanghai 200062, China

Nonlinear polaritons in metamaterials via plasmon induced transparency
Abstract: In recent years, much attention have been paid to the study on nonlinear properties in various metamaterials. In this talk, I shall give a simple introduction of our researches on nonlinear pulse propagations in metamaterials via plasmon induced transparency (PIT). We proposed a method to enhance Kerr nonlinearity and realize low-power gigahertz solitons via PIT. We showed that the PIT in such metamaterial can not only mimic the electromagnetically induced transparency in coherent three-level atomic systems, but also exhibit a crossover from PIT to Autler-Townes splitting. We further showed that the system also possesses a giant third-order nonlinear susceptibility and may be used to create plasmonic solitons and dromions with extremely low generation power. In addition, we showed that it is possible to realize a metamaterial analog of the four-wave mixing in coherent atomic systems and obtain vector plasmonic dromions in a metamaterial. Our study raises the possibility for obtaining strong nonlinear effect of gigahertz radiation at very low intensity based on room-temperature metamaterials [1-6]. ​

References
[1]. Zhengyang Bai, Chao Hang, and Guoxiang Huang, Opt. Express 21, 17736 (2013). ​
[2]. Zhengyang Bai, Guoxiang Huang, Lixiang Liu, and Shuang Zhang, Sci. Reports 5, 13780 (2015). ​
[3]. Zhengyang Bai and Guoxiang Huang, Phys. Rev. A 93, 013818 (2016). ​
[4]. Zhengyang Bai, Datang Xu, and Guoxiang Huang, Opt. Express 25, 785 (2017). ​
[5]. Qi Zhang, Zhengyang Bai, and Guoxiang Huang, Opt. Express 25, 25447 (2017). ​
[6]. Junfeng Su, Datang Xu, and Guoxiang Huang, ACS Photonics 5, 2496 (2018). ​

301/5 room​​ (Birzhevaya line, 14​)

19.11.2018 16:00
Boris Okorn
Researcher, University of Zagreb and Institut Ruder Boskovic

Can displacement current connect electronics to nano-photonics and vice versa?
Abstract: The concept of metatronics, that is supposed to brings the field of electronics to the ‘nanophotonic level’ has recently been proposed by prof. Engheta. Some of the envisaged applications of metatronics include all-optical chips, subminiature optical waveguides and filters, just to name a few. The basic pillar of metatronics is the ‘wire’ that guides the electric and magnetic displacement currents in the way analog to directional flow of electrons in an ordinary metallic wire. In this talk, the basic theoretical concept of an ‘optical electric/magnetic wires’ will be explained together with several experimental verifications performed at the University of Zagreb (UNIZG) and Rudjer Boskovic Institute (IRB). Finally, the ‘ reversed way’ of thinking that scales some ideas from metatronic back to RF and has led to the current fruitful collaboration between UNIZG, IRB and ITMO will be highlighted.​

301/5 room​​ (Birzhevaya line, 14​)

07.11.2018 12:00
Leonid G. Gerchikov
Peter the Great St.Petersburg Polytechnic University, St.Petersburg, Russia

From quantum to classical dipole plasmon resonances in nanoparticles
Abstract: Quantum effects in local surface plasmon excitations in free metallic clusters, metallic clusters embedded in a dielectric matrix, and highly doped semiconductor nanocrystals are considered. The goal of the study is to reveal the transition from quantum to classical regime of plasmon excitation under the increase of nanoparticle size. The main attention is focused on the size dependence of plasmon resonance frequency. Broadening of the plasmon resonance and anharmonic effects are also discussed. Two different types of plasmon resonances in bulk and surface doped nanocrystals are compared. Quantum treatment of plasmon excitations is done by means of many-body quantum mechanical approach.​ ​

301/5 room​​ (Birzhevaya line, 14​)

06.11.2018 14:00
Дмитрий Витальевич Татарников
д.т.н, профессор кафедры Радиофизики, антенн и микроволновой техники, Московский авиационный институт, Руководитель разработки антенн, Зам. Гл. Конструктора, Топкон Позишионинг Системз, г. Москва

Электродинамика и особенности разработки антенн высокоточного позиционирования
Abstract: 2226 room​​ (Lomonosova str. 9​)

29.10.2018 17:00
Nikolai Avdievich

Evaluation of Folded Dipole Antennas as Elements of Transmit and Receive Arrays for Human Head Imaging at 9.4T
Abstract: Presentation consists of two parts, which discuss use of dipole antennas as elements of transmit (Tx) and receive (Rx) human head array coils. Increasing the number of surface loops in a human head Rx-array improves the peripheral SNR, while SNR near the brain center doesn’t substantially change. Recent work on Ultimate Intrinsic SNR (UISNR) demonstrated that an optimal central SNR at ultra-high field (>7T) requires contribution of two current patterns associated with a combination of surface loops and dipole antennas. However, to incorporate multiple dipoles into a multi-row human head loop Rx-array, the dipole length has to be substantially reduced, which may compromise its performance. First part of the presentation presents an optimization of a short Rx-only dipole element and a construction of a novel human head phased array consisted of 8 TxRx surface loops and 8 folded Rx-dipoles. In the second part of the talk a novel design of a head Tx-array consisting of 8 longer folded dipoles is presented. Folded dipoles provide better decoupling between adjacent elements of the array as compared to the straight dipole antennas. New design also improves longitudinal RF magnetic field coverage and helps to minimize the maximum local SAR. ​

301/5 room​​ (Birzhevaya line, 14​)

24.10.2018 11:00
A.V. Poshakinskiy
Ioffe Institute, Saint Petersburg, Russia

Optomechanical Kerker effect
Abstract: We study theoretically the light scattering by a small particle with resonant dielectric permittivity that periodically moves in space. The crossover between the motion-induced Doppler effect and Raman scattering is revealed. The scattered light is shown to have strong forward or backward directivity, depending on the detuning between the light frequency and the permittivity resonance. The directivity is due to the motion-induced conversion of the electric dipole moment to a magnetic one, which gives rise to Kerker effect for a particle lacking magnetic response. Polarization conversion at scattering is also discussed. ​

301/5 room​​ (Birzhevaya line, 14​)

09.10.2018 12:00
Jacob B Khurgin
Johns Hopkins University Baltimore MD

Non-magnetic optical isolators: what works and what does not?
Abstract: Optical Isolators are essential components of all photonic circuits. Optical isolation means nonreciprocal propagation that requires breaking of time inversion symmetry. Usually isolation is achieved with magnetic field but recent years have seen an effort directed toward development of magnetic –field –free optical isolators, based on temporal modulation, optical nonlinearity, and a novel phenomenon of parity-time symmetry in systems with loss and gain. In this talk, following the short review of existing isolating devices, the performance characteristics of various non-magnetic schemes will be compared and the case will be made for the optical isolator based on second and third order nonlinearities that have good isolation and high dynamic range. ​

301/5 room​​ (Birzhevaya line, 14​)

08.10.2018 16:00
Barbara Cappello

Reducing radar cross section by anisotropic metasurface coating
Abstract: In the last years, electromagnetic metamaterials have been extensively studied thanks to their capacity of controlling and bending the propagation path of the electromagnetic waves in unprecedented ways. Among the different applications of metamaterials, cloaking is one of the most fascinating. In particular, mantle cloaking, differently from other techniques, has the advantage of suppressing the scattered field from the target object by using a 2D thin patterned metasurface, therefore reducing the cloak weight and thickness. In this talk we will address the problem of reducing the radar cross section of non-electrically small structures, focusing on the theoretical analysis of metallic cylinders mantle cloaking and on the design of an anisotropic metasurface based on a width modulated microstrip line.

10.09.2018 16:00
Nikolai Avdievich

Optimization of a Double-Tuned Human Head Transceiver Array for 31P Spectroscopic Imaging at Ultra-High Field
Abstract: Imaging other than hydrogen nuclei, i.e. X-nuclei, is often difficult due to a lower gyromagnetic ratio, and, thus lower SNR. Therefore, SNR enhancement with increasing the magnetic field strength, B0, one of the advantages of ultra-high field (UHF, > 7T) human MRI, is very critical for X-nuclei imaging. To provide high-resolution anatomical human head imaging and shimming without removal of the coil or patient from the magnet, double-tuning of the RF coil is necessary. Chemical shift spectroscopic imaging (CSI) of a human brain at 1H and X-frequencies provides valuable information in study and diagnostics of many diseases and pathologies, and currently was included in several clinical protocols. CSI also benefits from a whole-brain coverage, which requires using of multi-element RF array circumscribing the entire head. In the presentation I discuss several designs for human head 31P/1H arrays as well a new design optimized for UHF CSI. The new 20-channel array provides full brain-brain coverage at both frequencies, relatively high and uniform SNR at 31P-frequency, and high transmit efficiency at 1H-frequency.

22.08.2018 11:00
Anton Souslov
James Franck Institute, University of Chicago

Chiral active metamaterials
Abstract: Active liquids are composed of self-driven microbots that endow the liquid with a unique set of mechanical characteristics. We design metamaterials using polar active liquids, i.e., liquids that flow spontaneously and without the need of external forcing. Specifically, we create chiral steady-state flow using periodically shaped microchannels. This induced flow gives rise to topologically protected density waves, which are robust against both disorder and backscattering. Furthermore, active liquids composed of self-spinning rotors are chiral by design, a feature reflected in their constitutive relations. In two dimensions, the viscosity of such liquids includes an extra component called odd (or Hall) viscosity. Odd viscosity provides no energy dissipation, but couples pressure to vorticity. We explore how this coupling may be exploited to design self-assembled hydraulic cranks that convert between linear and rotational motion in microscopic machines powered by active rotors. ​

515 room​​ (Birzhevaya line, 14​)

21.08.2018 11:00
Institute for Theoretical Physics, Stony Brook University, New York

Квантовые флуктуации в спиновых цепочках
Abstract: Spin chains are models of realistic quantum devices. They can be realized in optical lattices and appear in un-isotropic crystalline structures in solid state. History of quantum entanglement and spin chains will be explained. The entanglement measures the level of quantum fluctuations. Different spin chains will be reviewed. The chains with highest level of fluctuations will be singled out. ​

515 room​​ (Birzhevaya line, 14​)

14.08.2018 11:30
Denis Bandurin
School of Physics & Astronomy, University of Manchester, Manchester M139PL, United Kingdom

Electron Hydrodynamics in Graphene: Fundamentals and Application
Abstract: Transport in systems with many particles experiencing frequent mutual collisions (such as gases or liquids) has been studied for more than two centuries and is accurately described by the theory of hydrodynamics. It has been argued theoretically for a long time that the collective behaviour of charge carriers in solids can also be treated by the hydrodynamic approach. However, despite numerous attempts, very little evidence of hydrodynamic electron transport has been found. Graphene encapsulated between hexagonal boron nitride (hBN) offers an ideal platform to study electron hydrodynamics as it hosts an ultra-clean electronic system with electron-electron collisions being the dominant scattering source above liquid nitrogen temperatures. In the first part of my talk we will discuss why electron hydrodynamics has not been observed before and how it manifests itself in electron transport. Furthermore, it will be shown that electrons in graphene can behave as a very viscous fluid (more viscous than honey) forming vortices of applied electron current1 . In the second part, we will discuss the measurements of the viscosity of an electron fluid by its superballistic flow through graphene point contacts2 . Then we will talk about the behaviour of electron fluids in the presence of magnetic field where I will report the experimental measurements of the odd (Hall) viscosity in two dimensions3 . This dissipationless transport coefficient has been widely discussed in theoretical literature on fluid mechanics, plasma physics and condensed matter physics, yet, until now, any experimental evidence has been lacking, making the phenomenon truly a unicorn. Last but not least, we will discuss how electron hydrodynamics can be used for the development of resonant plasmonic terahertz detectors where I report some recent progress in this direction4,5. ​

301/5 room​​ (Birzhevaya line, 14​)

09.07.2018 17:15

Russian-French workshop 2018 Institut Jean Lamour – ITMO University
Abstract: Program: Russian-French workshop 2018

29.06.2018 10:00
G. V. Astakhov
Helmholtz-Zentrum Dresden-Rossendorf, Institute of Ion Beam Physics and Materials Research, 01328 Dresden, Germany

Engineering of spin defects in silicon carbide for quantum applications
Abstract: Building quantum devices based on silicon carbide (SiC) is highly desirable, facilitated by established SiC CMOS technology. Optoelectronic SiC devices have already been demonstrated, however, the signal-mediating quantum defects are usually introduced in a semi-random manner, by bulk electron or neutron irradiation. We present the controlled generation of quantum centers in silicon carbide (SiC) by focused proton beam in a noncomplex manner without need for pre- or post-irradiation treatment. The generation depth and resolution can be predicted by matching the proton energy to the material’s stopping power, and the amount of quantum centers at one specific sample volume is tunable from ensembles of millions to discernible single photon emitters. We identify the generated centers as silicon vacancies through their characteristic magnetic resonance signatures and demonstrate that they possess highly coherent spin properties even at room temperature.​ ​

301/5 room​​ (Birzhevaya line, 14​)

21.06.2018 10:00
Marina Semina
Ioffe Institute

Generation of the second harmonic in Rydberg excitons in copper oxide
Abstract: Nonlinear optical phenomena are of particular interest, since they are extremely sensitive to the symmetry of the system, to the features of electronic spectrum, and to the properties of light-matter interaction. The report presents the theory of second harmonic generation on excitons in semiconductors, with the special attention paid to copper oxide crystals, where the exciton effects manifest themselves most vividly. The plan of the report as follows:
1. The symmetry analysis.
2. Two-photon absorption in semiconductors.
3. The mechanism of second harmonic generation in a noncentrosymmetric crystal.
4. Quadrupole and magnetodipole second harmonic in centrosymmetric copper oxide.
5. Polariton effects in the second harmonic. ​

301/5 room​​ (Birzhevaya line, 14​)

20.06.2018 11:00
Kirill Koshelev
ITMO Univ

Designing functional dielectric metasurfaces for linear and nonlinear wavefront control
Abstract: We discuss the general theoretical approach for advanced control of light wavefront with full phase and amplitude engineering by using resonant dielectric metasurfaces. We show how efficient functional metadevices, such as lenses, deflectors, vortices or holograms, can be realized at the nanoscale in both linear and nonlinear regime. Our analysis includes but is not limited to the concepts of the resonant phase accumulation, the multipolar decomposition, the Green’s function apparatus and the lattice summation.​ ​

301/5 room​​ (Birzhevaya line, 14​)

09.06.2018 14:00
Andrey Aktersky

Low-energy singlet excitations in square lattice Heisenberg antiferromagnetic with 1/2 spin
Abstract: We present an approach based on a dimer expansion that describes low-energy singlet excitations (singlons) in spin-12 Heisenberg antiferromagnet (HAM) on simple square lattice. An operator ("effective Hamiltonian") is constructed whose eigenvalues give the singlon spectrum. In the case of simple square lattice the "effective Hamiltonian" looks like a Hamiltonian of a spin-1/2 magnet in strong external magnetic field and it has a gapped spectrum. It is found that singlet states lie above triplet ones (magnons) in the whole Brillouin zone except in the vicinity of the point (π,0), where their energies are slightly smaller. Based on this finding, we suggest that a magnon decay is possible near (π,0) into another magnon and a singlon which may contribute to the dip of the magnon spectrum near (π,0) and reduce the magnon lifetime. It is pointed out that the singlon-magnon continuum may contribute to the continuum of excitations observed recently near (π,0). In the second part, we study singlet low-energy spectrum of HAM on square lattice with nearest- and frustrating next-nearest-neighbor exchange couplings J1 and J2. It is well known that a non-magnetic phase arises in this model at 0.4≲J2/J1≲0.6 sandwiched by two N'eel ordered phases. In agreement with previous results, we observe a first-order quantum phase transition (QPT) at J2≈0.64J1 from the non- magnetic phase to the N'eel one. Large gap (≳0.4J1) is found in the singlet spectrum at J2<0.64J1 that excludes a gapless spin-liquid state at 0.4≲J2/J1≲0.6 and the deconfined quantum criticality scenario for the QPT to another N'eel phase. We observe a first-order QPT at J2≈0.55J1 presumably between two non-magnetic phases. ​

515 room​​ (Birzhevaya line, 14​)

25.05.2018 10:00
Oleg Utesov
Saint Petersburg University of Nuclear Physics. Research Associate.

Novel approach to Raman spectra of nanoparticles
Abstract: Crystalline nanoparticles, including semiconductor particles and nanodiamonds, are actively investigated nowadays for applications in novel materials, quantum computing, biology and medicine. One of the important methods of nanoparticles study is Raman spectroscopy. In comparison with bulk material the Raman peak frequency in nanoparticles is downshifted and the peak is asymmetrically broadened. These effects are straightly related with the finite particle size. This opens up a possibility to use Raman spectroscopy for measuring nanoparticles sizes. The standard tool for crystalline nanoparticles Raman spectra (RS) theoretical analysis is semi phenomenological phonon confinement model (PCM). It is based on the assumption of Gaussian decay of vibrations from the particle center to its boundary. Further analysis of this model shows that it contains some important flaws. We propose a new model free of PCM disadvantages using the system microscopical parameters. The only adjustable parameter of the theory is the phonon linewidth. In order to obtain the particle vibrational eigenmodes we use the dynamical matrix method. Then, the bond polarization model is utilized to calculate the particle RS. With the usage of some averaging procedure, we also formulate our method in analytical form. The latter does not require cumbersome calculations but loses some information about the spectrum. In the framework of our theory we successfully describe the recent experimental data on nanodiamonds powders with sizesvarying from 1 to 10 nm, while PCM is unable to fit them.
In the second part of the work we propose a simple method for obtaining nanoparticles RS. It is based on solving boundary value problem, which resembles Klein-Fock-Gordon equation. The results of this approach reproduce the numerical ones with the high accuracy. So, instead of solving dynamical matrix, one can solve simple Laplace equation. In the framework of this theory we investigate the question of particles shape influence on RS and we obtain some interesting results.​ ​

515 room​​ (Birzhevaya line, 14​)

23.05.2018 11:00
Andrey Bogdanov
ITMO University

High-Q optical states in subwavelength resonators
Abstract: We reveal a novel mechanism for achieving high Q factors of subwavelength resonators by realizing the regime of bound states in the continuum. ​

515 room​​ (Birzhevaya line, 14​)

18.05.2018 12:00
A. R. Vilenskiy
Bauman Moscow State Technical University, Samsung Research Institute Russia

Design techniques for wideband low-profile phased antenna array elements with wide-angle beam steering: a review
Abstract: We consider design techniques for low-profile phased antenna arrays (PAA) with wideband wide-angle beam steering performance. Special attention is given to printed patch radiators, performed on suspended substrates with probe-fed or aperture-coupling excitation method. Another approach, based on application of cavity-backed patch resonators, for simultaneous bandwidth enhancement and mutual coupling reduction is considered. Additionally, we address the problem of substrate surface waves suppression by employment of low-elements EBG (electromagnetic band-gap) structures for some existing printed PAA element designs. The given design examples are illustrated by results of full-wave simulations inside Floquet channel, experimental results of measured PAA fragments of finite size are also presented. Finally, we dwell on some effective techniques, built on spectral-domain Galerkin’s method, for full-wave analysis of both reflective and active printed PAA elements. ​

515 room​​ (Birzhevaya line, 14​)

16.05.2018 10:00
Leonid Golub
Ioffe Institute, St.Petersburg

Magnetospatial dispersion of quantum wells
Abstract: Polarization conversion of light reflected from quantum wells governed by both magnetic field and light propagation direction is observ​​ed.We demonstrate that the polarization conversion is caused by the magnetospatial dispersion in quantum wells which manifests itself in the reflection coefficient contribution bilinear in the in-plane components of the magnetic field and the light wave vector. The magnetospatial dispersion is shown to arise due to structure inversion asymmetry of the quantum wells. The effect is resonantly enhanced in the vicinity of the heavy-hole exciton. We show that microscopically the magnetospatial dispersion is caused by the mixing of heavy- and light-hole states in the quantum well due to both orbital effect of the magnetic field and the in-plane hole motion. The degree of the structure inversion asymmetry is determined for GaAs/AlGaAs and CdTe quantum wells. ​

515 room​​ (Birzhevaya line, 14​)

15.05.2018 12:00
Dmitry Mikulik
Assistant-doctorant Laboratory of Semiconductor Materials Ecole Polytechnique Fédérale de Lausanne

Functional characterization of semiconductor nanostructures
Abstract: This talk will consist of two parts, each dedicated to functional characterization of nano-micro structures, such as GaAs nanowires (NWs) and Si micropillars (MPs). These methods address the requirements for characterizing nanostructures with high aspect ratio (HAR) and large array, thus tend to be a standard characterization in NW based devices. The first part focuses on a characterization of GaAs NW based solar cell structures by means of conductive-probe atomic force microscopy (C-AFM). Using this method, we explain how non-uniformity in electrical properties of NW p-n junctions in array can be quantified by different regimes in C-AFM, such as current scanning or single NW IV characterization. Also, we show that the small fraction of low performing NWs cannot determine the overall performance, but non-sensitive to light NWs can act as a leakage paths and drastically reduce the photovoltaic properties of the device. In the second part we introduce electrochemical impedance spectroscopy (EIS) for a characterization of the interfaces in oxide-semiconductor nanostructures. Surface passivation by ALD oxide is one of the option to suppress enhanced surface recombination in nano/micro structures due to high surface area. Despite complications with passivation step itself, analysis of the effect on interface defects requires advanced characterization. Standard capacitance-voltage (C-V) measurements require completion of the studied structure with metal gate. In HAR nano/micro structures metallization of the surface leads to discontinuity of the layer and difficulties with the area determination. By providing liquid electrolyte conformal contact, we have access to the full surface area of the HAR nanostructures thus able to quantify surface passivation by oxide layer. As an example of the characterization, we provide an analysis of the Al2O3 passivation of Si MPs, where we found the benefit of the low-temperature controllable thermal oxidation of Si MPs just before the ALD process.​ ​

515 room​​ (Birzhevaya line, 14​)

14.05.2018 10:00

С 24 по 27 мая в Хуанчжоу, Китай пройдет международный симпозиум The international Symposium On Plasmonics and Nano-photonics (iSPN2018)
Abstract: http://www.ispn2018.com/index.asp?navid=1

It will include but not limited to the following topics: Nanophotonics and Micro/Nano Optics, Metamaterials and Metasurfaces, Spin Photonics and Spin Optic, Plasmon-induced chemistry, Quantum Plasmonics, Emerging concepts in plasmonics, Optical force and manipulation, Spaser and Plasmon laser. Details are given during the conference.\

Являясь периодической международной конференцией по плазмонике, iSPN стремится создать платформу для ученых в области электромагнетизма и плазмоники для обсуждения последних результатов исследований, обмениваясь идеями и вдохновляясь новыми идеями в моделировании, изготовлении и тестировании фотонных материалов, структур, устройств и систем и их приложений.

Симпозиум будет включать следующие тематики: нанофотоника и микро / нанооптика, метаматериалы и метаповерхности, спиновая фотоника и спиновая оптика, химия плазмон-индуцированных процессов, квантовая плазмоника, новые концепции плазмоники, оптическая сила и манипуляция, лазер Spaser и Plasmon. Подробная информация будет обновляться во время конференции.

Один из основных докладов представит Павел Александрович Белов, главный научный сотрудник кафедры нанофотоники и метаматериалов, декан физико технического факультета, руководитель проекта "Диэлектрические и гибридные наноантенны для многофункциональных сенсоров"

https://metalab.ifmo.ru/program/ в рамках Федеральной целевой программы Министерства науки и образования Российской Федерации. Тема доклада "Recent progress in silicon-based nanophotonics".

11.05.2018 14:00
Алексей Алексеенко
Заместитель директора инжинирингового центра "М2М" ИТМО

Истории разных проектов
Abstract: Расскажу об опыте реализации проектов в различных средах: наука, R&D, производство, финансовый сектор. Обозначим основные признаки построения успешных историй. ​

440 room​​ (Birzhevaya line, 14​)

20.04.2018 11:00
Dr. Oleksandr Kyriienko
Fellow at NORDITA, KTH and Stockholm University, Stockholm, Sweden

Nonlinear opto- and electromechanics
Abstract: In this colloquium I will talk about the advances in the field of quantum optomechanics. This area of research, based on the radiation pressure-based interaction between optical and mechanical degrees of freedom, has shown to be tremendously useful, with applications ranging from gravitational wave detection to ultraprecise atomic sensing. In the talk I will concentrate on the novel types of the optomechanical coupling, which inherently exploit nonlinearity. First, a hybrid semiconductor-based setup will be discussed, showing the appearance of the dissipative coupling type in both linear and quadratic order. Next, I will introduce the interactive type of coupling for systems with modulated Kerr nonlinearity. Finally, I will show that electromechanical systems with quadratic interaction type can allow for the detection of a single mechanical quanta, thus allowing to test quantum physics at macroscale. ​

424 room​​ (Birzhevaya line, 14​)

20.04.2018 10:00
Research fellow, The Lebedev Physical Institute of the Russian Academy of Sciences​

NV center in diamond as a versatile platform for various quantum applications
Abstract: NV center in diamond is most studied and promising color center in diamond. It is of interest for various quantum applications ranging from single color center as a nanolocalized sensor of various fields or quantum computing and communication platform to micron size medium and large bulk ensembles of NV centers for ultraprecise sensors. In this talk results on broadband enhancement of single photon emission from NV center in diamond placed in the vicinity of hyperbolic dispersion will be highlighted, followed by results on coupling single NV center to tapered optical fiber and measuring its fluorescence quantum properties with superconducting single photon detector. To address challenge of ultraprecise sensors based on dense NV ensembles several attempts were made. Among them creation of efficient high- volume uniform ceramic MW antenna, creation of high quality diamond plates with good spin properties and high content of color centers, coherent control of N14 nuclear spin ensembles. Together these efforts pave the way towards creation of nuclear enhanced bulk sensors.

424 room​​ (Birzhevaya line, 14​)

10.04.2018 12:00
Gleb B. Sukhorukov
School of Engineering and Materials Science, Queen Mary, University of London

Polymer based microstructures as systems for controlled synthesis of nanoparticles, sensing, depot for chemicals and remote controlled delivery systems for drug and biological cells
Abstract: The presentation highlights recent advances in polyelectrolyte multilayers with particular attention in areas of polyelectrolyte multilayer structures on patterned surfaces, fabrication of microchambers with responsive properties, controlled in-situ synthesis of carbon nanoparticles and in vivo application of multilayer capsules. Polyelectrolyte multilayers can be deposition onto widely used PDMS stamps forming so called microchamber structures enabled to accommodate various biologically active molecules. Entrapment of water soluble molecules into sealed chambers is performed by depositing hydrophobic layer as polylactic acid on the top of multilayers and water soluble molecule make precipitate inside wells upon drying. Sealing results on formation of microsized air-bubble what can keep water soluble molecules inside the chamber until it released. In case of carbon source in polyelectrolyte multilayer such as dextran the hydrothermal synthesis results on formation of fluorescent carbon nanoparticles which can make the films conductive, fluorescent and responsive to light and ultrasound. Polyelectrolyte capsules can be responsive to remote physical signalling including magnetic field, light and ultrasound and in perspective also radiowaves. The perspectives of biomedical application of remote activation and microchambers and capsule delivery and microchamber activation are discussed.

515 room​​ (Birzhevaya line, 14​)

06.04.2018 10:30
Alexey V. Lukoyanov
M.N. Miheev Institute of Metal Physics of Ural Branch of Russian Academy of Sciences, Yekaterinburg, Russia

Computational modeling of new materials accounting for electronic correlations
Abstract: To describe the physical properties of materials, ab initio approach is commonly employed. Most methods are based on density functional theory. However, for many transition metal compounds, such as oxide compounds, electronic correlation effects cannot be neglected. During the last decades, to cope with this problem, a number of theoretical methods have been developed. Among them, DFT+U and DFT+DMFT methods are commonly used to take into account electronic correlations and describe magnetic and spectral properties of many correlated compounds. Several illustrations for DFT+U and DFT+DMFT results will be given, including 3d transition metal oxide systems with spin and metal-insulator transitions and compounds based on f metals. ​ Please, pay attention, that the th. seminar is compulsory for theoretical crystals!

515 room​​ (Birzhevaya line, 14​)

16.03.2018 10:45
Кондратов Алексей Владимирович
ФНИЦ «Кристаллография и фотоника» Институт кристаллографии им. А.В. Шубникова РАН

​Interaction of light and metamaterials with negative refraction and extreme optical chirality
Abstract: A complex approach to the theoretical study of 3D-chiral plasmonic nanohole arrays is presented, including the reconstruction of a real structure shape using AFM data, full-scale FDTD simulation, and coupled-mode model approximation. Prospects of using metal-hole arrays for the enhanced optical detection of molecular chirality in nanosized volumes are investigated. The ambiguity of the macroscopic description of light pressure on a continuous medium is discussed, including the case of negative refraction. It is shown that, although there exists a continuum of formally correct formulations, one can adopt the appropriate form of the macroscopic field stress tensor that allows a unified description of pressure during elementary light-matter interactions, such as reflection, refraction, absorption.

440 room​​ (Birzhevaya line, 14​)

16.03.2018 10:00
Ekaterina Khestanova
PhD, the University of Manchester

Recent advances in isolation and manipulation of atomically thin layers
Abstract: Isolation of single layer graphene in 2004 was only the tip of the iceberg that today is known as “2D materials”. In a little more than a decade the range of crystals that can be exfoliated down to single layer thickness and re-stacked to form van der Waals heterostructures has expanded significantly. However, atomically thin metals that can host such electron phases as superconductivity and charge density waves have not been investigated due to their sensitivity to ambiental oxygen and moisture. Recently this challenge has been overcome by a new method that involves mechanical exfoliation and fully motorized manipulation of atomically thin layers in inert atmosphere. In this talk I will describe such experimental setup and overview electron transport properties of van der Waals heterostructures with atomically thin superconducting NbSe2 prepared using the described setup. Additionally, I will briefly discuss how the methods of 2D crystals' manipulation can be applied to epitaxial perovskite thin films.

440 room​​ (Birzhevaya line, 14​)

02.03.2018 10:00
Pavel Ginzburg
Tel Aviv University

From optomechanical micro-robotics to RF metamaterial-based devices
Abstract: Recent activities of ‘Dynamics of Nanostructures’ Laboratory, encompassing optical and RF divisions, will be reviewed. The optical part of the presentation will concentrate on recent progress in optomechanical manipulation of micron-scale swimmers with holographic optical tweezers and auxiliary plasmonic structures. Some aspects of fluorescent lifetime imaging in application to temperature sensing will be discussed. The microwave part will be focused of metamaterial-based super-scatterers, radar-based mapping of multiple rotating objects, and multifunctional metasurfaces for imaging applications.

440 room​​ (Birzhevaya line, 14​)

19.02.2018 15:00
Vasily Kravtsov
Research Assistant​, University of Colorado at Boulder, USA

Nonlinear optical imaging and coherent femtosecond spectroscopy on the nanoscale
Abstract: Optical properties of many macroscopic systems are defined by the ultrafast dynamics of electronic, vibrational, and spin excitations localized on the nanoscale. Harnessing these excitations is a long-standing goal in science and technology, however challenging due to the lack of spectroscopic techniques that can resolve processes simultaneously on the nanometer spatial and femtosecond temporal scales. I will describe fundamental principles, implementation, and experimental demonstration of a novel type of ultrafast microscopy based on the concept of adiabatic plasmonic nanofocusing. A combined few tens of nanometers and few femtoseconds spatio-temporal resolution is achieved through nonlinear optical four-wave mixing response generated by compressed surface plasmon polaritons on a metallic near-field probe. This work opens up new avenues for probing and control of ultrafast coherent dynamics in materials.

515 room​​ (Birzhevaya line, 14)

16.02.2018 10:00
Nanooptomech Lab, ITMO University

Mesoscopic models in near-field light-matter interactions processes
Abstract: The Purcell effect for an emitter near the interface of two media and its application to optomechanical problems are considered. A mesoscopic model of a discrete-continuous medium is developed, it is shown that taking into account the discreteness of the medium near the emitter leads to a significant correction of the spontaneous decay rate. The Purcell effect for a moving emitter is considered and the possibility of extracting information about the motion of the emitter from the radiation spectrum is shown.

09.02.2018 10:00
Hannes Jonsson
Danmarks Tekniske Universitet, DTU

Towards optimal mean field theory of electronic structure, beyond Kohn-Sham DFT and Hartree-Fock
Abstract: In the basic description of electronic systems, each electron is taken to be subject only to the average interaction with the other electrons, i.e. a mean field approximation. The many electron wave function is then constructed from one-electron wavefunctions that are often referred to as ‘orbitals’. A variational optimization of an antisymmetrized product of orbitals gives Hartree-Fock (HF) theory which in some sense appears to be the optimal mean field theory. While molecular structure is quite well predicted by HF and the orbital energies can be used to estimate electronic excitations and photoelectron spectra, the total energy and, thereby, bond energy is not accurate. Kohn-Sham density functional theory (KS-DFT), is much more widely used today. It is also a mean field theory based to some extent on orbitals but gives a better estimate of the total energy, while orbital energies are inaccurate. HF and KS-DFT have several other shortcomings, for example an overemphasis on electron localization by the former and an overemphasis on delocalization by the latter. Is it possible to develop a mean field theory that gives accurate total energy as well as useful orbital energies and a proper balance between localized and delocalized states, thereby providing an optimal mean field theory, more accurate than either KS-DFT and HF? Since our intuition is based strongly on the concept of orbitals and the computational effort of higher level methods increases rapidly with the number of electrons, it seems worthwhile to seek such an optimal mean field theory. A promising approach appears to be an energy functional with explicit orbital density dependence (ODD). This expanded functional form makes it possible to avoid the self-interaction error inherent in KS-DFT while the computational effort still scales as the number of electrons cubed. Functionals formed by applying the Perdew-Zunger self-interaction correction [1] to KS-DFT functionals are examples of ODD functionals. While they do not represent optimal mean field theory, they give encouraging results and could be used to guide the development of such a theory. Various results obtained recently using a fully variational implementation of PZ-SIC applied to gradient dependent KS-DFT functionals and complex valued orbitals will be given in this presentation and some suggestions for further work towards an optimal ODD functional discussed. The calculations presented include atomization energy of molecules [2], localized and delocalized charge states in a cation [3], dipole bound anion [4], Rydberg excited states of molecules [5], electron holes in crystalline oxides [6] and magnetic properties of small transition metal clusters. [1] J.P. Perdew and A. Zunger, Phys. Rev. B 23, 5048 (1981). [2] S. Lehtola, E.Ö. Jónsson and H. Jónsson, Journal of Chemical Theory and Computation 12, 4296 (2016). [3] X. Cheng, Y. Zhang, E. Jónsson, H. Jónsson and P.M. Weber, Nature Communications 7, 11013 (2016). [4] Y. Zhang, P. M. Weber and H. Jónsson, J. Phys. Chem. Letters 7, 2068 (2016). [5] Y. Zhang, S. Deb, H. Jónsson and P.M. Weber, J. Phys. Chem. Letters 8, 3740 (2017). [6] H. Gudmundsdóttir, E. Ö. Jónsson and H. Jónsson, New Journal of Physics 17, 083006 (2015).

05.02.2018 14:00
A. Ivinskaya
Nanooptomech Lab, ITMO University

Plasmonic substrates and hyperbolic metasurfaces for flexible optomechanical manipulation
Abstract: Invention and further development of lasers brought into consideration many practical applications, which changed our life quite significantly. One of the remarkable phenomena with far going outcome is the ability to manipulate mechanical motion of small objects with focused laser beams. The field of optical tweezing, pioneered by A. Ashkin back at 1970, quickly became one of the widely used tools in biophysical research and many other areas. The ability to control mechanical path of small objects on demand opens a room for variety of novel investigations. My report is focused at a way for achieving another degree of freedom in optical manipulation and takes it towards flexible manipulation of nanoscale objects. In particular, auxiliary substrates were considered and their impact on optical forces was analyzed. Surface waves, supported by metal substrates were shown to tailor optical forces with remarkable property of switchable repulsion and attraction. Highly accurate size-dependent sorting of nano-scale particles was proposed. The interplay of optical trapping and anti-trapping enables achieving 1nm resolution in sorting-based applications. Optical binding of two nanoparticles at plasmonic substrate improves particle localization in dimer configuration several times. Particles can be bound on distances close to diffraction limit and SPP waves strongly influence dimer axis orientation. Another substrate which will be considered for optomechanical applications is multilayer stack which supports hyperbolic modes. Hyperbolic substrates allow for operation in a broad wavelength range. Almost any metal can comprise multilayer because volume modes are less affected by material losses. Elegant analytical theory and its application to different systems paves the way to use uniform and nanostructured substrates for opto-mechanical applications.

23.01.2018 12:00
Arseny Alexeev
University of Exeter

Tunable Plasmonic Nanogratings Enabled by Phase-Change Materials
Abstract: Phase-change chalcogenide alloys, such as Ge2Sb2Te5 (GST), have very different optical properties in their amorphous and crystalline phases. The fact that such alloys can be switched, optically or electrically, between such phases rapidly and repeatedly means that they have much potential for applications as tunable photonic devices. Here we incorporate chalcogenide phase-change films into a metal-dielectric-metal nanogratings and design perfect absorbers and beam steering devices for operation at technologically important near-infrared wavelengths, specifically 1550 nm. For perfect absorbers, we conduct an in-depth analysis of how design parameters of the structure influence the performance of the final devices. In particular, we show (both by modelling and through experiments) how one can achieve critically coupled absorbers and absorbers with desired quality factors. Then, we report on the design, fabrication, and characterization of innovative, non-volatile and reconfigurable beam steering nanogratings. Our devices reflect an incident optical beam in a mirror-like fashion when the phase-change layer is in the crystalline state, but reflect anomalously at pre-designed angles when the phase-change layer is switched into its amorphous state

19.01.2018 10:00
Mikhail V. Zyuzin
ITMO University, Russia

Interaction of nano- and microparticles with cell cultures and their bioapplications
Abstract: The interfacing of colloidal nano-, microsystems with cell cultures is now well into its second decade. The usage of particles has a various beneficial characteristics that make them attractive for a wide range of technologies. In this report my goal is to highlight how biological media could change the physicochemical properties of colloids, how colloids are internalized by cells, how to distinguish between internalized and membrane-attached colloids, and how stability of colloids may vary upon cell internalization. At the end, the some applications of microparticles as drug delivery carriers will be shown.

22.12.2017 11:00
Alexander Khanikaev
The City University of New York, USA ITMO University, Russia

Topological photonics
Abstract: Originating from the studies of two-dimensional condensed-matter states, the concept of a topological order has recently been expanded to other fields of physics and engineering, particularly optics and photonics. Topological photonic structures have already overturned some of the traditional views on wave propagation and manipulation. The application of topological concepts to guided wave propagation has enabled novel photonic devices, such as reflection-free sharply bent waveguides, robust delay lines, spin-polarized switches and non-reciprocal devices. Discrete degrees of freedom, widely used in condensed-matter physics, such as spin and valley, is now entering the realm of photonics. In this talk, I will summarize the latest advances in this highly dynamic field, with special emphasis on our recent works related to two- and three-dimensional all-dielectric topological structures, as well as spin and valley, polarized one-way Klein tunneling in topologically nontrivial systems.

15.12.2017 10:00
Pavel Bessarab
research assistant professor University of Iceland, Science Institute & Nanophotonics and Metamaterials Department, ITMO University

Thermally activated transitions in magnetic systems and long time scale spin dynamics
Abstract: Magnetic systems with several stable states characterized by distinct magnetic orderings are particularly important for the technological applications as they can in principle be used to code, store and process data. However, the preparation of a magnetic system in a particular state can be destroyed by spontaneous, thermally activated transitions to other available states. These transitions are typically rare events on the time scale of oscillations of the magnetic moments, making direct simulations of spin dynamics an impractical way to calculate transition rates. This separation of time scales, however, makes it possible to apply statistical approaches to study long time-scale spin dynamics. Development and implementation of such statistical methods will be presented in the lecture. Applications of the methods to various systems, including thermally-active artificial spin ice, magnetic nanoclusters on a surface and skyrmions, will be discussed.

08.12.2017 10:00
P. A. Belov, D. A. Zuev, S. V. Makarov

Seminar Novel fabrication methods of advanced nanostructures for sensor applications
Abstract: The program of the seminar is attached: Program of the seminar

01.12.2017 10:00
Alexander Agashkov
PhD, senior researcher, National Academy of Sciences of Belarus

Characterization of optical properties of metamaterials by interferometry
Abstract: Experimental methods used extensively for determining negative index of refraction in metamaterials, such as negative refraction, superlensing, R-T method and direct measurements (interferometry) are analyzed. New interferometric setups for measuring the negative length of the optical path are proposed and discussed.

17.11.2017 11:10
Prof. Constantin Simovski
Aalto University, Finland

Self-Oscillating Wireless Power Transfer
Abstract: Conventional wireless power transfer systems consist of a microwave power generator and transmitter located at one place and a microwave power receiver located at a distance. Here we show that wireless power transfer can be realized as a single "distributed" microwave generator with an over-the-air feedback, so that the microwave power is generated directly at the place where the energy needs to be delivered. We demonstrate that the use of this paradigm increases efficiency and dramatically reduces sensitivity to small displacement of the transmitting and receiving antennas, variations in load and power, and possible presence of obstacles between the antennas

17.11.2017 10:00
Институт Физики им Л.В. Киренского, Федеральный исследовательский центр, Красноярск

Near-bound states in the radiation continuum in circular array of dielectric rods
Abstract: We consider E polarized bound states in the radiation continuum (BICs) in circular periodical array of infinitely long N dielectric rods. We find that each true BIC which occurs in the infinite linear array finds its counterpart in the circular array with extremely large quality factor to define them as the near-BICs.We argue that the quality factor of the symmetry near-BICs behave as $e^{\lambda N}$ where $\lambda$ is a material parameter dependent on the radius and refraction index of the rods. We find also numerically the non-symmetry protected near-BICs tuned by the radius of rods. They are localized with exponential accuracy outside the circular array but fill whole inner space of the circular array forming near-BICs with orbital angular momentum.

10.11.2017 10:00
Alexander N. Poddubny
Ioffe Institute, ITMO University

Routing emission of light source near the surface by magnetic field
Abstract: Magneto-optical phenomena such as Faraday and Kerr effects play a decisive role for establishing control over polarization and intensity of optical fields propagating in a medium. Intensity effects where the direction of light emission depends on the orientation of the external magnetic field are of particular interest since they can be used for routing the light. Here, we report on a new class of transverse emission phenomena, where directionality appears perpendicular to a magnetic field and manifested for the light source located in the vicinity of the surface. In collaboration with experimental group from the Technical University of Dortmund we demonstrate routing emission for localized excitons in a diluted-magnetic-semiconductor quantum well. The directionality is significantly enhanced in hybrid plasmonic semiconductor structures where plasmonic spin fluxes at the metal-semiconductor interface in angle resolved far field emission are detected.​

03.11.2017 09:30
Mikhail Titov
NM, ITMO

Antiferromagnetic spintronics: can you make memory better?
Abstract: Antiferromagnets are materials with a so-called hidden magnetic order. This means that they have magnetic domains with a distinguished spin direction, but the magnetization is zero, so that it is impossible to detect such domains by measuring the magnetic moment. Partly, therefore, antiferromagnets were considered interesting, but absolutely useless for practical purposes by materials, in contrast, for example, from ferromagnets. During just one year the situation changed dramatically. Now antiferromagnets are considered the basis of future electronics and the main contenders for the creation of superfast and compact memory and even logical elements with terraced speed. In this report, I will talk about the main achievements of antiferromagnetic spintronics and those scientific problems in this field that, in my opinion, are of fundamental interest.

20.10.2017 11:10
Anna Andreychenko
new employee of the Metamaterials Laboratory

Use of waveguide principles for high field MRI and more…
Abstract: A radio-frequency (RF) signal wavelength of proton MRI at 7T becomes comparable to the circumference of the human MR scanner bore (1 m vs. 1.9 m) and the bore starts to act as a cylindrical waveguide for the RF signal. Moreover, in human tissue the RF wavelength shrinks to about 15 cm only. The operating wavelength shrinkage at 7T challenged the traditional design of large volume RF probes which was based on near field coupling and was successfully used at lower magnetic field strengths. On the other hand, because of the relatively small wavelength, microwave engineering principles could be borrowed to design novel RF probes. This opened a new RF research area for investigation and was called travelling wave NMR or waveguide MRI. In our work we explored waveguide principles and applied them for human body MRI at 7T and 9.4T. Three key attributes for any high field RF probe were addressed from the waveguide perspective: efficiency, signal uniformity by means of shimming and RF tissue heating. At the end I will give a short overview of my clinical MR experience: MR spectroscopy at 7T, a thermal noise based motion sensor (noise navigator) and bone marrow segmentation by means of MRI only.

20.10.2017 10:00
Вадим Леонидович Ушаков
ведущий научный сотрудник Курчатовского комплекса НБИКС-технологий НИЦ «Курчатовский институт», Москва, Россия.

Нейрокогнитивные исследования на основе метода МРТ

11.10.2017 11:40
Dr. Gerardo Guillén
Director of Biomedical Research Centro de Ingeniería Genética y Biotecnología (CIGB), Cuba

Biomedical Research Innovative pipeline at the Centre for Genetic Engineering and Biotechnology in Havana

11.10.2017 10:30
Alexander V. Uskov
Leading Researcher, P.N. Lebedev Physical Institute, Moscow, Russia ITMO University, St-Petersburg, Russia

Nanoscale contact as a source of plasmons for plasmonic nanocircuits
Abstract: Electrically driven optical antennas are attracting much attention, in particular, due to necessity to develop integrated electrical source of surface plasmons for future plasmonic nanocircuitries. By default, this term denotes a metal nanostructure, in which electromagnetic oscillations at optical frequencies are excited by electrons, tunneling between metallic parts of the structure when a bias voltage is applied between them. Instead of relying on an inefficient inelastic light emission in a tunnel gap, we are suggesting to use ballistic nanoconstrictions as the feed element of an optical antennas in order to excite electromagnetic plasmonic modes. Similarly to tunneling structures, the voltage applied at the constriction falls over the contact of nanoscale length. Electron passing through the contact ballistically can gain the energy provided by the bias ~1eV and exchange it into an mode of the optical antenna. We discussed the underlying mechanisms responsible for the optical emission, and show that with nanoscale contact, one can reach quantum efficiency orders of magnitude larger than with standard tunneling structures.

05.10.2017 12:00
A.A. Baikov Institute of Metallurgy and Material Sciences of Russian Academy of Science

Additive manufacturing in bone tissues engineering and diagnostics
Abstract: The present work is targeted to shortening of rehabilitation time and life quality improvement of the patients with bone tissue diseases through implementation of personalized tissue-engineered methodology and lab-on-the-chip technologies. Bone damage due to either pathology or trauma is very common. Its repair involves costly medical and/or surgical intervention, several human resources and a great deal of suffering for the patients: in many cases, tissue grafts are required to achieve functional recovery. Moreover, the presently available grafting techniques are only partially successful, and this is due to both the length and cost of the treatment as much as to the shortage of donor bone tissue. Tissue engineering approaches represent an effective alternative means of repair for bone damage and would provide a high social benefit. Tissue engineering approaches are foreseen as the use of scaffolding material in combination osteogenic factors. Personalized tissue-engineered systems for tissue engineering must ensure high quality, reliability, sustainability and cost-effectiveness of the individual’s life, providing a new, advanced level of the medical assistance in therapy and surgery. The task of obtaining a set of guiding design principles for scaffold design is clearly difficult because multiple stimuli are often operating simultaneously. A personalized approach based on additive manufacturing, i.e. three-dimensional printing, will help to provide a treatment option for bone defects based on the individual anatomical properties of the patient. The current work presents a novel, simplified concept of designing anatomically shaped bone constructs. This will allow for solving the inverse problem of designing a complex three-dimensional architecture for bone scaffolds, i.e. the problem of machining porous structures from bulk material. This approach allows to program the fabrication of the particular bone-mimicking architectures of the scaffolds that provide an optimal environment for a facilitated and faster “critical size” bone healing. Thus, this proposed state-of-the-art approach serves as most promising option for the successful solution in “critical size defects” in bone tissue engineering. It provides the opportunity to design the bone construct to adequately mimic the patient’s anatomy. This lecture is addressed of the own work related to the development and optimization of three-dimensional printing processes to fabricate novel scaffolds and the overview of technology for fabrication of cell-based bone repair and diagnostics systems (lab-on-the-chip technologies).

18.09.2017 15:30
Dmitry Skryabin
University of Bath and ITMO University

Introductory course to nonlinear optics
Abstract: "These lectures are part of the introductory course ""Photonics"", which is read to physics students at the University of Bath in the UK in the first semester of the fourth year. Studying this material allows students to get further through basic textbooks and monographs on nonlinear optics, and, in the future, to begin studying the scientific literature. To complete the course successfully, you need to know the general course of physics, common for the first two years of physical or engineering science education. This includes optical part, the Maxwell equations and their basic properties, as well as basic knowledge on methods for solving differential equations in ordinary and partial derivatives. Parts of the course requiring knowledge of quantum mechanics are not included in this abbreviated version."

15.09.2017 13:11
Zoran Eres
Ruđer Bošković Institute, Zagreb, Croatia

Graphene production at home in do-it-yourself CVD reactor
Abstract: Graphene draws considerable attention in science of new materials due to its outstanding properties. However, there are not many international companies that have it on their sales list – on world flee market eBay there are only two sellers that sell single layer CVD graphene with average price of 40 USD/cm2. “Graphene supermarket” company, with its big inventory list, have average price of 10 USD/cm2. Average cost of production, estimated at 1 USD/cm2, opens a question: Can you make money by doing science? In this talk I will present complete buildup process of low-cost do-it-yourself CVD reactor for graphene synthesis with all steps firmly explained. Majority of construction parts were bought of-the-shelf in local domestic supermarkets. Raman spectrum of produces samples confirms high quality single layer graphene with low concentration of defects which is suitable for use in scientific research.

23.08.2017 11:30
Thierry Belmonte
Research Director, University of Lorraine, Institut Jean Lamour, Nancy, France

"The Institut Jean Lamour: A young lab with a long history" (the talk is devoted to experimental works of the group)
Abstract: The Institut Jean Lamour was created from the merging of five laboratories in Nancy, France to form one the biggest research unit in our counrty. With about 515 people, the IJL has just been given a brand new building especially designed to welcome one of our major facility: the TUBE. With more than 20 ultra-high vacuum devices mounted on a 70-m long tube built to inter-connect them, this facility was constructed to synthesize and characterize nanomaterials on-demand. Research activities are led by 23 research groups organized into 4 scientific departments dealing with Physics of Matter and Materials, Chemistry and Physics of Solids and Surfaces, Materials Science and Engineering - Metallurgy, Nanomaterials, Electronics and Living Systems Department and 9 competence centers. A specific focus will be made on works in the field of nanoscience, metamaterials and plasmas.

23.08.2017 11:10
Dr. Alexandre Nomine
Postdoctoral Research Associate University of Lorraine, France

Synthesis of Nanoparticles by electric discharges in liquids
Abstract: Electric discharges in liquids are promising for the production of Nanoparticles (NPs) with high yields (up to 17g/h). Moreover a wide range of nano-objects can be created, from 1 or 2D materials to core-shell nanoparticles. However, the plasma-material interactions that give rise to NPs remain complex and incompletely understood. The present talk will review the progresses and challenges in plasma diagnostics and their interactions with materials.

23.08.2017 10:00
Dr. Alexey Vagov
University of Bayreuth, Germany

Path integral approach for the dynamics of small externally driven quantum systems coupled to a continuum
Abstract: Precise knowledge of the time evolution of small quantum systems interacting with a continuum of excited states of the embedding environment is necessary in many practical situations. One example is the dynamics of a strongly confined quantum dot coupled to phonons and placed in a cavity with quantized electromagnetic modes. Real-time path integral offers a numerically exact method to obtain the dynamics of the reduced density matrix of such systems. The method takes into account non-Markovian memory effects appearing due to the interaction with the continuum of excitations. The approach is also extended to take into account non-Hamiltonian contributions to the dynamics. In the talk I will describe details of the formalism and give examples of practical calculations, results of which can be used to achieve a desired quantum state of the system.

Room 301/5 at Birzhevaya line, 14

30.06.2017 10:00
Anna Baldycheva
University of Exe​ter, UK

Graphene and 2D materials for net generation opto-electronics and photonics
Abstract: The abstract can be found here.

23.06.2017 11:10
Julia Burunkova, PhD, assistant professor
ITMO University

Polymer nanocomposites for photonic sctructures recording by multibeam interference holography
Abstract: The presented investigations relate to the development of new polymer nanocomposite materials and technologies for direct, one-step fabrication of photonic elements like gratings, integrated elements, photonic crystals. Our nanocomposites contain SiO2 and Au nanoparticles as well as luminescent materials and are sensitized to UV, blue and green laser illumination. They are optically transparent with low scattering, biocompatible. The presence of gold nanoparticles and possibility to excite plasmonic effects can essentially influence the polymerization processes, the behavior of initiators, the spatial redistribution of nanoparticles in the nanocomposite during the recording, luminescent parameters of nanocomposites. 1-,2-3D photonic structures were recorded in the developed materials.

23.06.2017 10:00
Dmitrii Maksimov, Senior Researcher
LV Kirensky Institute of Physics, Krasnoyarsk, Russia

Bound states in the continuum and light localization in dielectric arrays
Abstract: We consider light trapping by structural resonances in linear periodic arrays of identical high-index dielectric elements. As the basic elements both subwavelength spheres and rods with circular cross section are investigated . When the array is infinite it is known to support bound states in the radiation continuum (BSCs), i.e. structural resonances with infinite life-time embedded into the continuous spectrum of scattering states. Two classes of the BSCs can be identified, namely, topologically and symmetry protected states. In case of arrays of dielectric spheres we show that there is a Bloch guided BSC mode which is stabilized by a topological singularity in space of the resonance coupling strength. We demonstrate numerically that this Bloch BSC can be employed for guiding light pulses above the line of light. If the infinite array is terminated at both ends to form a finite chain of dielectric elements the BSCs become high-Q resonances. We evaluate the asymptotic behavior of the Q-factor of such resonances against the number of elements in the array. We demonstrate numerically that under illumination by a plane wave nite arrays of 10-15 silicon nanospheres can be used to enhance the amplitude of the impinging light at least by order of magnitude in the visible-to-near infrared range when the material and geometrical parameters of the systems are tuned to the structural resonance associated with a BSC.

31.05.2017 10:00
Dr. David Ben Dahan
CNRS Research Director, Center for Magnetic Resonance in Biology and Medicine(CRMBM)/CEMEREM, CNRS, Aix-Marseille University, Marseille, France

Magnetic Resonance Imaging and Spectroscopy in Neuromuscular Disorders
Abstract: 10.00 – 10.45
Lecture 1. Investigation of muscle energetics using 31-phosphorus spectroscopy
The pathological process in neuromuscular disorders leads to a variety of alterations within muscle fibers including atrophy, inflammation, fatty infiltration etc. which can eventually affect muscle energy production. Taking advantage of development regarding MR scanners and dedicated radiofrequency antennas, 31-Phosphorus spectroscopy has emerged, a few decades ago, as a tool of choice for the non-invasive investigation of muscle energetics. Thanks to the detection of a few high-energy phosphate metabolites and the capacity of measuring intracellular pH, 31-P MRS has been used to document energy production in patients with muscle disorders and trained subjects. The purpose of the first lecture will be to present the 31-P MRS approach and the corresponding results regarding muscle energy production.

11.00 – 11.45
Lecture 2. MR imaging acquisition and post-processing issues
Over the last decade, dedicated MRI tools have been designed in order to quantify more or less specifically the histological abnormalities occurring in patients with neuromuscular disorders with the aim of providing sensitive biomarkers which could be used for diagnostic and therapeutic follow-up purposes. During the second lecture, the corresponding tools will be presented. Once the MR images are acquired a large amount of work is needed if one aims at tracking these abnormalities at the level of individual muscles or muscle groups. Atlas-based segmentation is a powerful method for automatic structural segmentation of several sub-structures in many organs. However, so far, very few studies have assessed this method for skeletal muscle segmentation. The second part of the lecture will be dedicated to the presentation of the multiple steps of an atlas-based pipeline we have developed for segmentation of quadriceps muscles from magnetic resonance images. Based on largely acknowledged parameters such as the DICE index, we will also illustrate the potential and the accuracy of different versions of the pipeline for longitudinal follow-up in healthy volunteers and in patients for whom an additional component of fat infiltration has to be taken into account.

26.05.2017 11:20
Athanasios G. Polimeridis
Skolkovo Institute of Science and Technology, Moscow

Fast Integral Equation Methods in Engineering Design: From Global Maxwell Tomography and Ultimate Bounds for MRI Coil Performance to Quantum Fluctuations
Abstract: The abstract can be found here

26.05.2017 10:00
Alexander.V. Poshakinskiy and Alexander N. Poddubny
Ioffe Institute, St. Petersburg

Optomechanics with multiple quantum wells
Abstract: The abstract can be found here

16.05.2017 16:00
Dr. Nikolai Avdievich
Senior Research Scientist, High-Field MR Center, Max Planck Institute for Biological Cybernetics, Tübingen, Germany, Institute of Physics, Ernst-Moritz-Arndt University Greifswald, Greifswald, Germany

Design of Radiofrequency Coils for MRI: Main Approaches and Modern Trends
Abstract:

#### Schedule

###### Tuesday, 16.05, room 301/5
16.00-16.45
Lecture 1. MRI RF Coils: Surface Coils
Matching and tuning of the RF surface coil. Reciprocity theorem, RF coil transmit efficiency, SNR. Q-factor, Optimization of the RF surface coil. Transverse RF surface coils. Tx/Rx linear and quadrature RF coil operations. Components and circuits for RF surface coils.
17.00-18.30
Lecture 2. RF Coil Components
Transmission lines: VSWR, Reflection coefficient, Impedance, Smith Chart (Introduction), S-parameters, Matching and tuning of the RF surface coil, Components and circuits for RF surface coils, TR Switch, Baluns (Cable traps), Hybrids (Splitters).

###### Wednesday, 17.05, room 440
14.30-15.15
Lecture 3. MRI RF Coils: Volume Coils
General method of designing a homogeneous volume coil. Single-mode volume coils. Multiple mode volume coils. Birdcage coil volume coil. TEM volume coil. Half-volume multimode coil. Perturbation method.
15.30-17.00
Lecture 4. Tx-only/ Rx-only RF Coils and Interfacing to the Scanner
Detuning methods (active, passive), Design of Tx-only (Rx-only) RF surface coils, Design of Tx-only (Rx-only) RF volume coils, Rx-only phased arrays, Preamplifier decoupling, Cable rooting, Interfacing the RF coil to the scanner, Parallel reception, Components and circuits for Tx-only/ Rx-only RF coil.
17.15-18.00
Lecture 5. Phased Array Decoupling Methods
Decoupling of receive-only (Rx) arrays. Decoupling methods common for both Tx and Rx arrays. Resonant Inductive Decoupling (RID). Amplifier decoupling of Tx arrays. Decoupling (detuning) of Rx and Tx arrays (interarray decoupling). Decoupling b/w 1H- and X-nuclei arrays (double-tuned arrays). Geometrical Decoupling.

###### Thursday, 18.05, room 301/5
14.30-15.15
Lecture 6. Phased Array RF Coils
Building block -a single element of an array. Design of Tx-only/ Rx-only arrays (Example). Transmit vs Transceiver arrays. MRI at ultra-high field –advantages and challenges.
15.30-16.15
Lecture 7. Optimization of the Transmit and Receive Performance of the Transceiver Phased Array for Human Brain Imaging at Ultra-High (> 7T) Fields (UHF)
Maximum local SAR. Decoupling of transceiver array. Various optimization scenarios. Transmit efficiency. Receive performance. Longitudinal coverage. Final Array Design.
16.30-17.15
Lecture 8. Multi-Tuned Coils
Useful circuits and review (trap design, matching). Double-tuning of the same surface loop. Design ideas and criteria (match, efficiency). Double-tuning of 2 separate surface loops. Various designs of double-tuned coils. Double-tuned volume coils. Double-tuned arrays.

04.05.2017 10:00
Naumova Elena
Rzhanov Institute of Semiconductor Physics Siberian Branch of Russian Academy of Sciences

Design and investigation of chiral THz Metamaterials based on nanofilm microspirals
Abstract: The synopsis can be found here.

18.04.2017 15:00
Prof. Silvio Hrabar
Professor of Electrical Engineering, University of Zagreb, Unska 3, 10000 Zagreb, Croatia

Abstract: This course reviews the field of RF and microwave metamaterials and related structures. In the first part, the emphasis is given both on basic background physical phenomena and real-word engineering applications. In the second part, the inevitable connection between RF and microwave metamaterials and plasmonic/graphene/optical metamaterials and metatronics is analyzed. In the third part, the basic idea and applications of active metamaterials is discussed. Finally, some emerging trends in active/reconfigurable metamaterials are highlighted.
You are welcome to visit his lectures accordingly the Shedule.

05.04.2017 10:00
Andrei Gorodetsky
ITMO University, Lancaster University, Cockcroft Institute

Application of nanostructures for THz generation and detection enhancement
Abstract: In my talk, I will present our most recent results on advances in photonic THz generation and detection by using of nanosized structures. The talk includes two different approaches to nanostructure involvement: first, I will review the results on THz generation in InAs/GaAs quantum dot based photoconductive antennas, their strenghts and perspectives. Then, I will describe the advantages of Hybrid metallic photoconductive antennas that include both microsized THz antenna structure and optical nanoantennas, over conventional ones.

21.03.2017 12:55
Than Singh Saini
CSIR-Central Scientific Instruments Organization Sector-30, Chandigarh-160030, India

Photonic Crystal Fibers and Their Applications
Abstract: Photonic crystal fibers (PCFs) are a kind of specialty optical fibers that demonstrate a diversity of new and improved features beyond what conventional optical fibers can offer. In this talk, the PCFs and their applications in different fields will be discussed. Particularly Mid-infrared supercontinuum generation in PCFs and Slow-light generation in PCF will be the main focus of this talk.​

21.03.2017 12:30
Umesh Kumar Tiwari
CSIR-Central Scientific Instruments Organization Sector-30, Chandigarh-160030, India

Fiber Gratings beyond Communications
Abstract: Among the several fiber optic components used in fiber optic communication systems and in fiber optic sensors is the fiber grating. Fiber Grating sensors have emerged as potential sensing platforms for structural health monitoring, bio-sensing applications and harsh environment applications. Fiber Grating sensors are broadly classified into Fiber Bragg Grating sensors and Long Period Grating sensors. Generally, these sensors offer higher accuracy, longer stability, smaller size, immunity to electromagnetic interference (EMI) and the ability to measure ultra-high speed events and thus they surpass traditional electrical and mechanical sensors. These sensors owing to convenience of multiplexing in wavelength domain enable distributed sensing where multiple sensors are monitored by a single signal processor bringing cost-effectiveness. Development of FBG sensors for vibration measurement and crack identification has been carried out in CSIO. In the area of bio-sensing, Glucose oxidase (GOD) immobilized long period grating (LPG) fibers for the specific and sensitive detection of glucose have been proposed and experimentally demonstrated. Proposed technique can further be extended to develop LPG fiber based novel, sensitive and label free nanosensors for disease diagnosis and clinical analysis which will help to address social issues like adulteration, pathogen and pesticide detection in food and beverages.

21.03.2017 11:55
Samir K Mondal
CSIR-Central Scientific Instruments Organization Sector-30, Chandigarh-160030, India

Engineering optical fiber tip (antenna and negative axicon) for Nanophotonics/Photonics research
Abstract: Optical fiber tip appears to be ideal for optical probing. Interestingly, optical fiber tip can be modified to give unique shapes generating unique optical field patterns which may have significant impacts in photonics research and instrumentation. A state of the art etching technique under the influence of capillary action has been introduced for preparation of novel optical design at fiber tip, namely optical antennas (positive axicon) and negative axicon. The unique features of the naturally grown axicons make it very attractive for various applications both in near-field optics and far field optics. Few applications have been explored such as non-plasmonic optical tweezers, field enhanced second harmonic generation, optical coherence tomography imaging etc. The modified optical fiber tips appear to be very useful optical for interdisciplinary subjects of research.

21.03.2017 11:30
R.K. Sinha
CSIR-Central Scientific Instruments Organization Sector-30, Chandigarh-160030, India

CSIR-CSIO: Research and Development Activities
Abstract: This will be very general talk with a brief description of CSIR and research and developmental activities of my organization CSIO-Central Scientific Instruments Organisation which will also include R&D activities and facilities of Optics and Photonics activities with a view of enhancing collaborative research between CSIO and ITMO.

21.03.2017 10:30
D.D. Arnone (Chief Executive Officer Teraview Ltd)
Teraview Ltd

Terahertz generation and recent Terahertz applications in biomedicine and other areas
Abstract: Dear Colleagues,
We invite You to attend D.D. Arnone (Chief Executive Officer Teraview Ltd) short presentation of Teraview Ltd products and their applications - "Terahertz generation and recent Terahertz applications in biomedicine and other areas" in Department of Photonics and Optical Information Technologies ( Kadetskaya lin. V.O., 3B) lecture room 23 on March 21 at 10:30. Presentation time 30-45 min including questions.

10.03.2017 10:00
Pobegaeva Olga Andreevna
Deputy director of Saint Petersburg State Budgetary Agency "Information Metodical Centre", head of company "Sphere"

Objects of the patent law: Invention, Utility model, industrial design (examples and differences). Patentability. Patent investigations: content and procedure.

03.03.2017 10:00
Boris Afinogenov, PhD student
Moscow State University

Femtosecond nonlinear optical spectroscopy of photonic crystals in the presence of Tamm plasmon polaritons
Abstract: Abstract. I will present results on the study of optical and nonlinear-optical properties of photonic crystal/metal structures under conditions of the Tamm plasmon excitation. I will tell about (1) experimental determination of the TPP lifetime, (2) impact of the TPP excitation on the femtosecond response of PC/metal structures, (3) enhancement of the second and third optical harmonics generation in the presence of TPP, and (4) experimental observation of the TPP-surface plasmon hybrid state and its properties.

17.02.2017 15:10
Dmitry Zezyulin, postdoctoral researcher
Center for Theoretical and Computational Physics, University of Lisbon, Portugal

Solitons in parity-time-symmetric and asymmetric complex potentials
Abstract: The steadily growing interest to parity-time (PT-) symmetric systems has started out in non-Hermitian quantum mechanics, where complex potentials obeying PT symmetry can exhibit all-real spectra. Driven by the mathematical similarity between the quantum mechanical Schroedinger equation and dispersive wave models, the concept of PT symmetry later spread out to optics, Bose-Einstein condensates, and many other physical fields where the description of nonlinear effects is of profound importa​nce. PT-symmetric systems are characterized by a judicious balance between gain and loss. In optics, it can be implemented by a properly designed profile of the complex-valued refractive index. In an atomic condensate, PT symmetry corresponds to the situation where particles are injected into the system at some spot and are simultaneously eliminated from the condensate at a different spot, with the gain and loss rates being equal. Therefore, from the dynamical point of view, PT-symmetric systems are inherently open and dissipative. At the same time, PT symmetry gives rise to a wide array of new phenomena which have no counterparts in traditional dissipative systems. In our talk we will discuss one of these unusual features which is the existence of continuous families of PT-symmetric solitons (in contrast to traditional systems with gain and loss where dissipative solitons appear as isolated attractors). Moreover, we will demonstrate that there exists another class of generically asymmetric complex potentials which enjoy the same unusual property.

17.02.2017 14:00
Department of Laser Systems and Technologies, ITMO Univirsity

2D/3D photonics materials micro & nanostructuring by advanced laser technologies
Abstract: Short overview: - local oxidation of thin metal films, - control of porous glass density & corresponding properties, - phase-structure modification of photostructurable glass, - laser-induced microplasma and its application for transparent materials processing.

20.01.2017 11:00
Terekhov Pavel, PhD student
Nanophotonics and Metamaterials Department, ITMO University

Resonant forward scattering of light by high refractive-index dielectric nanoparticles with toroidal dipole contributions
Abstract: We demonstrate and investigate the Kerker-type effect in high-index dielectric nanoparticles for which the third order multipoles give a considerable contribution to the light scattering process. It is shown that the Kerker-type effect (strong suppression of the backward light scattering and, simultaneously, resonant forward light scattering) can be associated with the resonant excitation of toroidal dipole moment in the system. This effect is realized due to the interference of the scattered waves generated by electric, magnetic and toroidal dipole moments of high-index nanoparticles.

20.01.2017 10:00
Pr. Fedorov Boris Aleksandrovich
Laboratory of Structure Bioinformatic, ITMO University, Russia

Small-angle X-ray diffusive scattering. Basics, development and applications in ITMO University
Abstract: We show a basics of small-angle X-ray diffusive scattering, developement and applications this method in ITMO University for investigation structures of some synthetic and nature materials.

23.12.2016 11:00
Maxim Durach
Department of Physics, Georgia Southern University, USA

Transformation of Fundamental Properties of Light via Interaction with Nanostructured Metal
Abstract: Interaction of light and matter involves transfer of conserved quantities such as energy, momentum, angular momentum etc. Plasmon drag effect (PLDE), the giant enhancement of photoinduced currents in plasmonic metals at surface plasmon resonances (SPR), allows for a systematic study of these fundamental transfer processes. Understanding of exactly how to control this transfer through material properties, precise nanostructuring and/or illumination conditions in one of the main goal of photonics and will bring unprecedented advances in sensing, detection and processing of hybrid optoelectronic signals for applications ranging from new generation computers to electronic output optical biosensors and structured light detectors. Advanced design allows for creating ultimately thin metasurface wave plates, which are capable of complete transformation of polarization of light by 30 nm thick metasurfaces and at the same time makes possible mesoscopic metal-dielectric structures which exhibit optical neutrality, i.e. do not affect light passing through them.

16.12.2016 11:00
Nikita A. Olekhno, master student

2d-plasmons in a random impedance network model of disordered thin-film nanocomposites
Abstract: In the present talk, we will show that plasmon resonances in disordered nanocomposites can be studied by means of equivalent random impedance networks. A special attention is paid to the case of thin-film nanocomposites (or disordered metasurfaces) consisting of a mixture of conductor and insulator. As we will show, a widely used representation of such systems with square-lattice impedance networks implies two-dimensional Coulomb interaction and thus should be corrected. A new model is proposed, which takes into account three-dimensional nature of Coulomb interaction in thin films. Resonances in ordered films of finite thickness within this model correspond to a surface plasmon-polaritons, whereas resonances in systems, strongly confined to the plane, represent 2d-plasmons. Applying this model to a case of two-dimensional disordered systems we show, that at volume fractions of conductive phase below percolation threshold spectral gaps in the form of Lifshitz tails are present, whereas for fillings higher than percolation threshold a crossover between 2d-plasmons and localized resonances is observed. Lifshitz tail edge, as well as the crossover frequency, are both obey scaling relations near the percolation threshold.

09.12.2016 11:00
Prof. Sergiy Vorobyov
Aalto University

A signal processing perspective on MRI
Abstract: In this lecture the principles of magnetic resonance imaging will be presented from the perspective of signal generation and image formation, i.e., signal processing perspective. The basic physical principles behind signal generation in MRI yet will have to be briefly reviewed in a simplified form. These principles are magnetic polarization (achieved by applying very strong uniform magnet), excitation (achieved by using powerful radiofrequency transmitter), acquisition (achieved by applying gradient magnetic fields). It will be shown how based on these principles a signal can be generated and recorded. The rest of the lecture will be devoted to review of the basic principles for making use of nuclear magnetic resonance data. The key signal processing techniques used are: Fourier- or k-space and image formation from the k-space. The key parameters for sampling k-space are: resolution, contrast, field of view, bandwidth, time of acquisition, SNR. The relationship between these parameters will be informally discussed. The process called pulse sequence consisting of RF pulse transmission followed by acquisition will be explained, detailing to some extend only the basic T1, T2, STIR, and FLAIR pulse sequences.

09.12.2016 10:00
Dr. Redha Abdeddaim
Institut Fresnel

RF Field Homogenization in Ultra-High Field MRI
Abstract:
Due to B1+ inhomogeneity, brain images at 7T show important contrast heterogeneity. Many different approaches have been proposed to tackle this problem. The first one was to use High-Dielectric Constant (HDC) pads surrounding the region of interest to enhance locally the RF field. Second solution, called parallel RF transmission (pTx) has been then introduced. It consists of placing several RF transmitters around the subject, instead of a single one on standard MR systems. Taking advantage of RF interferences, it is possible to obtain a much more homogeneous excitation. These additional degrees of freedom provide better control of the magnetization. Third solution is to use metamaterial to interact with the magnetic field and increased the homogeneity. In this presentation, we address these different solutions and give examples of utilisation.

28.11.2016 12:00
Dr. Nico van den Berg and Dr. Alexander Raaijmakers
University Medical Center Utrecht, The Netherlands.

Lectures on new MRI research methods, MRI safety and novel radiofrequency systems of MR scanners
Abstract: On Monday, November 28, 2016 the honored experts in the field of MRI technology and methods from the University Medical Center Utrecht, Dr. Nico van den Berg and Dr. Alexander Raaijmakers will read lectures at ITMO University (Birjevaya line V.O. 14-16, room 301/5). The lectures will be devoted to new MRI research methods, MRI safety and novel radiofrequency systems of MR scanners.

Lecture timetable 12:00-13:00
Lecture 1. RF safety monitoring of parallel transmit MRI
With the arrival of parallel transmit MRI, the risk of localized RF tissue heating increases significantly. Current concepts to characterize RF tissue heating are not suited to monitor this more complex safety aspect. The lecture will discuss new directions in RF safety monitoring for MRI and will explore in particularly the role of EM simulation to characterize this safety aspect.
13:00-13:15 Coffee break
13:15-13:45
Lecture 2. Electrical Property tomography
At ultra high field MRI, the augmented electromagnetic interactions of tissue with radiofrequency fields, leads to unwanted standing waves compromising image quality and increased RF tissue heating. Rather than seeing this a nuisance, this also opens up opportunity to try to map the dielectric composition of the human body by mapping the RF field curvature with MRI. This lecture discusses the principles of this socalled Electrical Property Tomography and discusses recent progress on this topic.
13:45-15:00 Lunch
15:00-16:00
Lecture 3. RF coil array design
At ultrahigh field MRI, the Larmor frequency has increased to 300 MHz for 7 Tesla system. Systems with even higher field strengths have been installed in a small but increasing number of institutes. Such high frequencies require a different in comparison to classical system. The absence of a birdcage body coil makes alternative transmit solutions essential. Currently, most solutions have aimed at multi-transmit solutions. This requires the design of (local) transmit array elements that need to be balanced between efficiency and heat deposition.
16.00-16.15 Coffee break
16:15-16:45
Lecture 4. RF implant safety
More and more people are carrying medical implants. These may include passive implants such as cardiac stents, surgical screws or artificial hips. Active implants may include pacemakers and neurostimulators. Patients with such implants are likely excluded from MRI examinations, which may result in severely limited diagnostic capabilities in the case of future diseases or health issues. Therefore, implant manufacturers are creating more and more MRI compatible products. The RF safety certification of these products is a costly procedure. We have developed methods to assess RF safety of implants using MRI measurements rather than elaborate bench measurements. The advantages are that these methods could be extended to more realistic test scenarios up to even in-vivo safety assessment. This would allow the large patient population that is currently carrying uncertified implants to have access to MRI diagnostics.

17.11.2016 14:00
Denis V. Novitsky
B.I.Stepanov Institute of Physics, National Academy of Sciences of Belarus

Theoretical Studies of Short Pulse Interaction with Resonant Media and Nonlinear Photonic Structures
Abstract: In this talk, I will give a brief review of the results obtained in several recent years. Three directions of research will be discussed:
• (i) Studies of interaction of ultrashort laser pulses with resonant two-level media;
• (ii) Theoretical description of distributed-feedback dye lasing by polarization modulation;
• (iii) Investigation of nonlinear effects in such photonic structures as photonic crystals and metamaterials, with emphasis on short-pulse propagation and localization.

15.11.2016 13:30
Dr. Carlos Cabal Mirabal
Center for Genetic Engineering and Biotechnology, Havana, Cuba

Dr. Carlos Cabal Mirabal (Cuba, Havana) will read lectures in Nanophotonics and Metamaterials Department about Magnetic Resonance and its applications.
Abstract: The main goals of the course are to make introduction in the basics of MR theory, to explain the main principles of MR based techniques, to show perspectives and challenges which MR techniques are focused on.
Dr. Carlos Cabal Mirabal is a Titular Researcher of Center for Genetic Engineering and Biotechnology, Senior Professor in University of Havana, Merit of the Academy of Sciences of Cuba and Extraordinary Professor of the Faculty of Exact Sciences of the La Plata National University, Argentina.
Attention! The lectures are obligatory for master students of Nanophotonics and Metamaterials Department. Other participants must fill the form: Registration
All the lectures will be held in the office 301/5 (Birzhevaya line, 14)

Lectures timetable Tuesday, November 15 (1 lecture)
13.30-15.00
Introducton. MR Basic ideas. Spin Lattice and Spin Spin relaxation. Pulse sequences. Bloch equations. Magnetic Resonance Imaging.
Thursday, November 17 (2 lectures)
10.00-11.30
Magnetic relaxation mechanism in paramagnetic solution. Basic ideas. Density spectral function, correlation times, spin-lattice and spin-spin relaxation mechanism. The basic ideas of the contrast agent.The basic ideas of the contrast agent. Some MR applications.
11.30-11.45
Coffee break
11.45-13.15
MR and EPR studies of the hemoglobin polymerization in the Sickle Cell disease. Treatment approach.
Friday, November 18 (2 lectures)
14.00-15.30
Basic ideas of molecular MRI and Theranostic. Enhance the MRI sensibility.
15.30-15.45
Coffee break
15.45-17.15
Bio distribution and pharmacokinetic of uniform magnetic nano particles by MRI in vivo.
Thursday, November 24 (2 lectures)
10.00-11.30
Brain Tumor response and kinetic under treatment with monoclonal antibodies by T1,T2, FLSH, DWI, MRS images
11.30-11.45
Coffee break
11.45-13.15
Quantitative studies of the evolution of the diabetic foot lesion under Epidemical Grow factor treatment by MRI and optical methods.
Friday, November 25 (2 lectures)
10.00-11.30
MRI instrumentation. Cuban MRI project.
11.30-11.45
Coffee break
11.45-13.15
Third Biomedical Revolution. Regularities and tendencies. The images role.

07.11.2016 14:00
Danil Kornovan, 1-year PhD student
ITMO University

Light scattering and excitation transport in a 1D array of two-level quantum emitters in a presence of long-range coupling and spin-locking effect
Abstract: In the talk we will present a theoretical study on properties of a chain of two-level quantum emitters coupled to one dimensional nanostructures supporting a single propagating mode. The first part will be related to the case of an optical nanofiber and how a presence of long range dipole-dipole interaction of two-level systems affects its optical properties. The second part will be dedicated to temporal dynamics of a single excitation transport between emitters coupled through the guided mode of the structure in an asymmetric way - when a so-called spin-locking effect occurs – leading to an effective unidirectional transport.

07.11.2016 14:00
Ageyskiy Alexander, 4-year PhD student
ITMO University

Wire medium studies: past and present
Abstract: Wire medium is a famous metamaterial that breaks the diffraction limit and has a unique imaging properties. The analytical and numerical studies on half and quarter wavelength lenses made of this metamaterial performed. The influence of the host medium as well as the magnetic response from the thick wires noticed and investigated. The experimental study of the magnifying wire medium lens is targeted.

28.10.2016 10:00
K. N. Toosi University of Technology

Equivalent conductivity method: analytical solution for metasurface-based structures
Abstract: Equivalent conductivity method is an approach for analyzing metasurface-based structures, which relies on the derivation of equivalent conductivity containing the properties such as the geometry, periodicity, and the surrounding materials. Using this approach, one can calculate the equivalent conductivity for a single metasurface layer and then consider it in further analysis of multilayer structures. When the particles of metasurface play dipole role, one can describe the polarizability of them by a Lorentzian line shape. Then, Equivalent conductivity of the metasurface can be derived by considering the calculated polarizability. This analytical method can be extended to the multi-spectral inhomogeneous metasurfaces with various components. There is no spectral limitation in the proposed approach, and it can be used for design and analysis of devices based on homogeneous and inhomogeneous metasurfaces in any frequency range. Because of interesting properties of graphene, description of this method is made by considering an array of graphene nanodisks as a metasurface. Also, absorbers and cloaking structures consisting of homogeneous and inhomogeneous metasurfaces are designed as the examples of this method applications.

28.10.2016 10:00
Dr.Andrey Miroshnichenko
Australian National University, Australia

Observation of Anapole with Dielectric Nanoparticles
Abstract: Nonradiating current configurations attract attention of physicists for many years as possible models of stable atoms. One intriguing example of such a nonradiating source is known as “anapole”, which can be viewed as a composition of electric and toroidal dipole moments, resulting in destructive interference of the radiation fields. Here we demonstrate experimentally that dielectric nanoparticles can exhibit a radiationless anapole mode in visible.

28.10.2016 10:00
Olga Pobegaeva

Creation, safeguarding and commercialization of intellectual property
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

14.10.2016 10:00
Mikhail Sumetsky
Aston University

Nanophotonics of optical fibres
Abstract: Nanoscale effects in photonic structures fabricated from pure optical fibres are reviewed. In contrast to those in plasmonics, these structures do not contain metal particles, wires, or films with nanoscale dimensions. Nevertheless, a nanoscale perturbation of the fibre radius can significantly alter their performance. I consider slow propagation of whispering gallery modes along the fibre surface. The axial propagation of these modes is so slow that they can be governed by extremely small nanoscale changes of the optical fibre radius. The described phenomenon is exploited in SNAP (Surface Nanoscale Axial Photonics), a new platform for fabrication of miniature super-low-loss photonic integrated circuits with unprecedented sub-angstrom precision. The SNAP theory and applications are reviewed.

07.10.2016 11:00
Gorlach Alexey
Belorussian state university

Pulling Force in Quantum Mechanics
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

26.09.2016 14:00
Neil Roberts
University of Edinburgh

New developments in magnetic resonance elastography (MRE) measurement of tissue mechanical properties
Abstract: Magnetic Resonance Imaging (MRI) and X-ray Computerised Tomography (CT) have been essential in the identification and diagnosis of a wide range of disorders, although usually are insufficient in sensitivity for detecting subtle pathological alterations to the brain prior to the onset of clinical symptoms - at a time when prognosis for treatment is more favourable. In recent years, mechanical properties of the brain have been visualised and measured noninvasively with Magnetic Resonance Elastography (MRE) with the aim of increasing the potential for early diagnosis. The seminar will begin with an introduction to the various methods used for the acquisition and analysis of MRE data and studies that have specifically utilised MRE to investigate the human brain will be reviewed. Through the conversion of MRE-derived measurements to shear stiffness (kPa) and, where possible, the loss tangent (rad), a summary of results for global brain tissue and grey and white matter across studies will be presented for healthy participants. In addition the extent to which MRE has revealed significant alterations to the brain in patients with neurological disorders will be assessed and discussed in terms of known pathophysiology. Predictions will be offered regarding the trends for future MRE research.

26.09.2016 14:00
Danil Kornovan
ITMO University

Light scattering and excitation transport in a 1D array of two-level quantum emitters in a presence of long-range coupling and spin-locking effect
Abstract: In the talk we will present a theoretical study on properties of a chain of two-level quantum emitters coupled to one dimensional nanostructures supporting a single propagating mode. The first part will be related to the case of an optical nanofiber and how a presence of long range dipole-dipole interaction of two-level systems affects its optical properties. The second part will be dedicated to temporal dynamics of a single excitation transport between emitters coupled through the guided mode of the structure in an asymmetric way - when a so-called spin-locking effect occurs – leading to an effective unidirectional transport.

16.09.2016 10:00
Alexandra Kalashnikova
Ioffe Physical-Technical Institute

Optically driven magnons and phonons for ultrafast control of magnetic state of matter

12.09.2016 12:00
Stepan Boichenko
Irkutsk Branch of the Institute of Laser Physics of the Siberian Branch of the Russian Academy of Sciences

Laser-scanning confocal fluorescence microscopy based on elliptically polarized cylindrical vector beams as a tool for visualization of arbitrarily oriented single quantum emitters
Abstract: We theoretically study the visualization of arbitrarily oriented single quantum dipole emitters (single molecules, single quantum dots, single color centers, etc.) located in different layered media and in free space, performed by means of laser-scanning confocal fluorescence microscopy (LSCFM) based on elliptically polarized cylindrical vector beams (EPCVBs). In particular, it is demonstrated that one can exclude the dependence of the image intensity maximum on the emitter’s orientation for emitters located in free space and in 99%-collection-efficiency nanoantenna [Opt. Lett. 36, 3545 (2011)]. The problem of visualization of arbitrarily oriented single quantum emitters located in planar microcavities by means of EPCVB-based LSCFM is studied as well.

16.08.2016 14:00
Evgeny Pidko
ITMO University

Computational chemistry for rational design of functional materials
Abstract: In this lecture I will present an introductory overview of power, capabilities and limitations of modern quantum chemical techniques for studying reactivity and chemical properties of different classes of inorganic materials ranging from organometallic complexes to MOFs and zeolites. The subjects discussed in the lecture will include the methodological aspects of computational chemistry crucial for modeling extended chemical systems as well as recent relevant examples of application of computational methodologies for developing new concepts of catalytic reactivity. Emphasis will be made on the complementary use of experimental and computational approaches for unraveling molecular-level phenomena defining the specific functions of the materials.​

12.08.2016 14:00
Amir Boag
Tel Aviv University

Ultra-Wideband Nano-Antenna Arrays
Abstract: Efficient ultra-wideband nano-antennas are becoming key components for novel photonic applications, such as energy harvesting and optical sensing of particles, fluid refractive index, chemical and biological agents, etc. Downscaling the well-known configurations of metallic antennas from radio to the optical and infra-red (IR) frequencies offers unique advantages for many of these applications. Furthermore, metallic nano-antennas can be loaded with carbon nano-devices to provide specific functionality. Two types of ultra-wideband highly efficient nano-antenna arrays developed by our group will be described. Also, a novel technique for antenna and load impedance measurements using scattering data will be presented. Various applications of nano-antennas will be discussed.

01.08.2016 14:00
Denis Baranov
Moscow Institute of Physics and Technology

Linear and nonlinear light-matter interaction with all-dielectric nanoresonators
Abstract: High-index semiconductor nanoparticles form an alternative platform for boosting light-matter interaction at the nanoscale without plasmonic structures. Enhancement of optical response with such particles originates from excitation of their magnetic and electric Mie resonances. Here, I present our recent results on linear and nonlinear optical properties of resonant high-index particles. ​​ As an example of a linear effect, we overview the advances in enhancement of spontaneous emission with all-dielectric nanostructures. Furthermore, we have observed more than 100-fold enhancement of Raman scattering from single resonant Si nanoparticles. This observation is promising for various biological applications. ​Turning to the nonlinear side, we have developed the analytical model describing nonlinear transient response of a nanocrystalline silicon nanoparticle induced by electron-hole plasma generation. The model demonstrates the possibility of ultrafast reconfiguration of the scattering power pattern of single particles and asymmetric nanodimers, allowing for ultrafast nonlinear light routing. Our results prove the potential of silicon nanoparticles for the development of multifunctional nanoscale all-optical devices.

19.07.2016 10:00
Arseny Alexeev
University of Exeter

Phase-Change and Carbon-Based Materials: from Resistive Switching to Optoelectronic Applications
Abstract: Phase-change materials (chalcogenide alloys such as GeSbTe) and carbon-based materials (graphene oxide and amorphous carbon) are one of the most promising candidates for the emerging resistive switching memory devices. Under external stimulus, such as voltage or laser pulse, they undergo (partial) phase transition resulting in the change of both electrical properties, i.e. switching between states with low and high resistance, and optical characteristics of the media. Thus, phase-change materials were recently suggested for creating optoelectronic devices (e.g. tunable absorbers, phase modulators, optical memories) and for tunable metamaterials while carbon materials are already widely used for various electrical and optical applications. In this talk I will give an overview of the main research areas of our group and will present some recent results on optical applications of GeSbTe-based (meta)materials and resistive switching studies in graphene oxide.

19.07.2016 10:00
ITMO University

Design and modeling of UV projection optical system by using the elements of A.I. feature
Abstract: Design of new lithographic systems using starting configurations based on A.I. (artificial intelligence) feature of Synopsys software. Overview of Projection lithography development, the challenges and limits of present technology. By using the DSearch macro in Synopsys software was conducted research and method proposed in design of novel UV lithographic objectives which should simplify the work of optical designer in early stage of design.

06.07.2016 12:00
Dmitry Bykov
Image Processing Systems Institute RAS

Theoretical foundations of resonant gratings, implementing spatiotemporal transformations of optical signals
Abstract: The talk is focused on studying diffraction of light (optical beams, pulses, and plane waves) by resonant optical structures. The particular structures considered are diffraction gratings (photonics crystal slabs) and phase-shifted Bragg gratings. Resonant optical and magneto-optical properties of these structures are investigated by studying structures’ eigenmodes. In the first part of the talk, a brief introduction to the concepts of the grating's scattering matrix, quasiguided modes, and Fano resonances will be given. New methods for calculating eigenmodes of resonant structures will be presented. Spatiotemporal formulation of the coupled-mode theory will be used to obtain a generalization of the Fano line shape of the resonance. This generalization gives simple approximations of the grating’s spatiotemporal transmission spectrum (taking into account both frequency and direction of the incident light). In the second part of the talk, these approximations will be used to derive a general form of optical signal spatiotemporal transformation implemented by resonant optical structures. The particular transformations investigated are the temporal and spatial differentiation of an optical signal. The last part of the talk covers the study of magneto-optical effects in resonant optical structures. In particular, resonances of Faraday and Kerr effects are studied by analyzing structure’s symmetry properties.

08.06.2016 11:00
Irina Guzhova and Boris Margulis
Institute of Cytology RAS

Molecular chaperones as therapeutical targets
Abstract: Molecular chaperones play a key role in cell physiology, proliferation, activation and tumorigenesis. One of the major chaperones, heat shock protein 70 kD (Hsp70) is a typical Janus-like protein whose activation in cells affected by mutant or misfolded protein causes correction of the latter and can rescue neural cells from the deleterious effects of growing protein aggregates. Therefore the enhanced expression of Hsp70 in neural cells would be beneficial in therapy of brain disorders as well as of aging. This enhancement is achieved by the application of certain drugs inducing Hsp70 expression and some of these are at the stage of lab bench trials. To estimate the efficacy of anti-degenerative substances the special methods of photonics may be designed able to define protein aggregate growth dynamics possibly in single cells. Oncological pathologies is an extremely wide class of sicknesses differing in their origin, history, therapeutic strategy etc. In sick cells Hsp70 plays the protective role, and this counteracts the majority of anti-cancer factors used to selectively or indiscriminately kill tumor cells. Thus it is clear that Hsp70 expression or chaperonic function should be reduced by certain drugs firmly binding the protein. Since the protective function of Hsp70 is based on its interactions with the other cell proteins the tools are necessary to study such interactions. It is also important to generate assays with which one would be able to analyze binding of potential drug molecule to Hsp70. Hopefully, both classes of assays may be generated with the aid of biophotonic techniques.

20.05.2016 11:00
ITMO University, University of Sydney

Electromagnetic wave band structure due to surface plasmon resonances in a complex plasma
Abstract: The dielectric properties of complex plasma containing either metal or dielectric spherical inclusions (macroparticles, dust) are investigated. The focus is on surface plasmon resonances on the macroparticle surfaces and their effect on electromagnetic wave propagation. It is demonstrated that the presence of surface plasmon oscillations significantly modifies plasma electromagnetic properties by resonances and cutoffs in the effective permittivity. This leads to related branches of electromagnetic waves and to the wave band gaps.

17.05.2016 14:00
Svetlana Kuznetsova
N. I. Lobachevsky State University of Nizhny Novgorod

Magnetic resonances of axially symmetric dielectric particles and metasurfaces on their basis
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

17.05.2016 14:00
Alexey Shcherbakov
Moscow Institute of Physics and Technology

Efficient numerical methods for rigorous simulation of the light diffraction on periodic structures
Abstract: The talk presents a class of numerical methods, referred to as the Generalized Source Methods (GSM), for rigorous numerical solution of the elastic diffraction problem in the optical band for periodic structures. Methods possess asymptotically linear numerical complexity, and computational memory consumption, and allow for efficient parallelization on Graphical Processing Units. These properties enable the GSM to outperform other methods for complex grating diffraction simulation in diffractive and integrated optics.

17.05.2016 14:00
Yury Stebunov
Moscow Institute of Physics and Technology

Highly sensitive optical biosensors based on graphene oxide
Abstract: At present time, label-free biosensors are widely used in scientific and pharmaceutical research for analysis of biochemical reactions. This method allows to investigate on-rates and off-rates of different reactions between various substances such as RNA, DNA, proteins, including antibodies and antigens, viruses and bacteria. The applications of the novel biosensor chip based on graphene oxide will be demonstrated. Graphene oxide chips provide better sensitivity comparing to existing commercial sensor chips based on self-assembled monolayers and hydrogels.

17.05.2016 14:00
Dmitry Svintsov
Moscow Institute of Physics and Technology

Plasmons in van der Waals heterostructures
Abstract: The combination of graphene and related layered compounds provides an opportunity to fabricate van der Waals heterostructures: a new class of materials with tunable optical properties. The report will be devoted to the uncommon properties of plasmons in these structures: from deep subwavelength confinement of electromagnetic field to the possibility of quantum cascade plasmonic lasing.

12.05.2016 10:00
Fokin V.A.
Federal Alazov North-West Medical Research Centre

Clinical application of MRI: methodology, possibilities, equipment, trends

12.05.2016 10:00
Efimtsev A.Yu.
Federal Alazov North-West Medical Research Centre

Modern possibilities of MRI and neurovisualization

12.05.2016 10:00
Bogachev Yu.V.
Federal Alazov North-West Medical Research Centre

Magnetic resonance theranostics

12.05.2016 10:00
Sokolov A.V.
Federal Alazov North-West Medical Research Centre

MR spectroscopy in clinical practice

12.05.2016 10:00
Stas Glybovsky
ITMO University

Metasurfaces for MRI with 7 T fields

12.05.2016 10:00
Alena Shchelokova
ITMO University

Metaresonators for the improvement of signal-to-noise ratio of MR images

11.05.2016 15:00
Maxim Gorlach
ITMO University

Dynamic symmetry breaking in photo-metamaterials
Abstract: In this talk I will outline the calculation of effective material parameters of nonlinear metamaterials and discuss an effect of dynamic symmetry breaking in photo-metamaterials. The first part of the talk will cover the aspect of nonlinear metamaterials' homogenization taking into account spatial dispersion effects. It is demonstrated that nonlocality in nonlinear structures gives rise to a variety of new physical phenomena including generation of multiple harmonic beams with the same polarization and dependence of nonlinear susceptibilities on the direction of wave vector of the fundamental wave. The deviations from the local effective medium model in the vicinity of nonlinear inclusions resonances will be discussed. The second part of the talk is related to the phenomenon of dynamic inversion symmetry breaking in photo-metamaterials. Unit cell of such photo-metamaterial incorporates photodiode and light-emitting diode. It is demonstrated that additional optical interaction channel in such structures gives rise to the emergence of the nonzero second-order nonlinear suscepbility. Basing on the rigorous nonlocal homogenization approach we calculate effective nonlinear susceptibilities of photo-metamaterial and make suggestions on possible experimental observation of dynamic symmetry breaking.

22.04.2016 10:00
Alexander Khanikaev
City University of New York

Topologically nontrivial states of light and sound
Abstract: The past three decades have witnessed the discovery of Quantum Hall Effect (QHE), Quantum Spin Hall Effect (QSHE) and Topological Insulators (TIs), which transformed our views on the quantum states of matter. These exotic states are characterized by insulating behavior in the bulk and the presence of the edge states contributing to charge or spin currents which persist even when the edge is distorted or contains impurities. In the last few years, a number of studies have shown that similar “robust” conducting edge states can be implemented in classical systems. In this talk I will review development of this field with focus on photonic and acoustic topological structures with and without time-reversal symmetry that we have recently proposed. I will discuss recent experimental realizations of topological order for electromagnetic waves with the use of bianisotropic metamaterials at microwave frequencies. New practical designs of photonic and acoustic topological insulators and their possible applications will be presented. I will show that photonic and acoustic topological systems, with deliberately created distributions of synthetic gauge fields, offer an unprecedented platform for controlling light and sound, e.g. by enabling routing and steering of waves along arbitrarily shaped pathways without loss or backscattering.

13.04.2016 14:00
Polina Vabishchevich
Lomonosov Moscow State University

Femtosecond dynamics of optical, magneto-optical and nonlinear effects in plasmonic crystals and silicon nanostructures with Mie resonances
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

05.04.2016 14:00
Anton Nalitov
Université Clermont Auvergne and University of Southampton

Polaritonic topological insulator
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

05.04.2016 14:00
Mehedi Hasan
ITMO University

Topological properties of the illuminated arrays of mesoscopic rings
Abstract: Recently it has been shown that the Aharonov-Bohm effect can be optically induced in the mesoscopic rings. Motivated by the known connection between the Aharonov-Bohm effect and topology we studied the topological properties of the illuminated arrays of mesoscopic rings of various geometry. Firstly, it will be discussed how a one-dimensional array of coupled rings can change the electronic properties under the illumination of circular polarized light. The counter-propagating edge-currents in a one-dimensional chain will be discussed; this counter propagating edge-current motivates us to increase the dimensionality by one and looking for topological non-trivial properties – inspired by Haldane model. Then it will be discussed how the geometric Berry phase ( acquired due to the broken time-reversal symmetry ) in a two-dimensional array of polariton-rings results the emergence of quantum spin Hall phase. Topologically protected edge currents for both spins will be demonstrated. Finally we will discuss non-trivial properties of zigzag array of quantum rings.

28.03.2016 14:00
P.G. Kazansky
University of Southampton, Mendeleev University of Chemical Technology

Advancing the Art of Ultrafast Laser Writing in Glass
Abstract: Interaction of intense ultrashort light pulses with glass reveals new properties and phenomena, which challenge common beliefs in optics. Demonstrations of 3D nanograting formation and related self-assembled form birefringence uncover new science and applications including flat optics elements ex-ploiting the Pancharatnam-Berry phase. The S-waveplate (Southampton-Super-Structured-waveplate) is one of the examples of such elements, which can be used for creating axially symmetric polarization state and optical vortexes. The applications of S-waveplates range from material processing to micros-copy and optical trapping. Two independent parameters describing self-assembled form birefringence in quartz glass, the slow axis orientation and the strength of retardance, are also explored for the opti-cal encoding of information in addition to three spatial coordinates. The data optically encoded into 5D is successfully retrieved by quantitative birefringence measurements. The storage allows unprecedented parameters including hundreds of terabytes per disc data capacity and thermal stability up to 1000°. The demonstrated recording of the first digital documents, including the eternal copy of King James Bible, which will survive the human race, is the vital step towards an eternal archive. These and more recent demonstrations of ultrafast laser calligraphy and anisotropic photosensitivity in glasses are reviewed.

26.02.2016 10:00
Anvar Zakhidov
The University of Texas at Dallas and National University of Science and Technology MISIS in Moscow

Mysterious Physics in Hybrid Perovskite: Excitons vs Correlated e-h pairs, suppressed carrier recombination, superior lifetimes and diffusion lengths for higher efficiency solar cells
Abstract: The hybrid (organo-inorganic) lead-halide perovskites revolutionized the field of solar cell research due to the impressive power conversion efficiencies of up to 21% recently reported in perovskite based solar cells. This talk will present first the general concepts of excitonic photovoltaics, as compared to conventional Si-type solar cells, asking a question: is hybrid perovskite PV an excitonic solar cell or not? Then I will show our recent experimental results on the fast spectroscopy of excitons, magnetic field effect on generation of correlated (e-h) pairs. Also will discuss our Hall effect results, that allows to evaluate intrinsic charge carrier transport and direct measurements of mobility in these materials performed for the first time in steady-state dc transport regime. From these measurements, we have obtained the electron-hole recombination coefficient, the carrier diffusion length and lifetime. Our main results include the intrinsic Hall carrier mobility reaching up to 60 cm2V-1s-1 in perovskite single crystals, carrier lifetimes of up to 3 ms (surprisingly too long!), and carrier diffusion lengths as long as 650 m (huge if compared to organic and even best inorganic materials). Our results also demonstrate that photocarrier recombination in these disordered solution-processed perovskites is as weak as in the best (high-purity single crystals) of conventional direct-band inorganic semiconductors. Moreover, as we show in our experiment, carrier trapping in perovskites is also strongly supressed, which accounts for such long carrier lifetimes and diffusion lengths, significantly longer than similar parameters in the best inorganic semiconductors, such e.g. as GaAs. All these remarkable transport properties of hybrid perovskites need to be understood from fundamental physics point of view. Looks like we need some new concepts to explain the mysterious properties of hybrid perovskites. We suggest that some of this unusual properties can be attributed to a special type of “dipole rotational polaron” formed in their lattice due to interactions of charge with methyl-ammonium organic dipoles, each of 2.3 Debye. I will try to challenge the audience to think about other possible explanations, since I believe that superior behaviour can be explained only by introducing new physical concepts, such as solitons/kinks and bipolarons (in conducting polymers), Cooper pairs in superconductors or vortices in type 2 superconductors, as another example.

26.02.2016 10:00
Artur Ishteev
National University of Science and Technology MISIS in Moscow

Transparent CNT electrodes for perovskite solar cell tandems

17.02.2016 14:00
ITMO University

Biomaterials by the eyes of solution chemist: synthesis, properties and suggestions for collaboration
Abstract: Following our fruitful collaboration in inorganic materials, current report is addressed to another critical issue developing in SCAMT laboratory – biomaterials. We will speak about our last developments in this area: functionalized parenteral materials, thrombolytic and plaquelytic colloids and graft coatings, sol-gel assisted protein renaturation, biosensors, etc. All of the results will be accompanied by the new ideas for possible collaboration making them more physically saturated and interdisciplinary.

17.02.2016 14:00
Irina Khromova
Public University of Navarra, ITMO University

Studying terahertz resonators: the near-field approach
Abstract: I will discuss the opportunities and advantages of the near-field terahertz time-domain spectroscopy and microscopy for direct experimental studies of terahertz electromagnetic resonances occurring on a micrometre scale. Micro-resonators are at the heart of numerous promising terahertz solutions, including the emerging metamaterial approach. Experimental studies of micrometre-scale terahertz resonances are essential, yet inaccessible to common far-field spectroscopic techniques due to extreme sensitivity requirements. The near-field approach allows for mapping the near-field patterns of terahertz resonant modes excited in individual conductive or insulating micro-objects. It gives access to essential parameters of micro-resonators, including their resonance frequency, local field enhancement and quality factors. Depending on the underlying physics of observed terahertz resonances, it allows for material and structural characterisation of micro-objects.

15.02.2016 14:00
S. Arakelyan

New physical principles of hybrid elements of photonics and optoelectronics creation based on laser-induced nanocluster structures with controlled technology
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

12.02.2016 10:00
M. Glazov
Ioffe Physical Technical Institute RAS

Coherent spin dynamics and optical control of spins in semiconductor nanostructures
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

04.02.2016 16:00
M. V. Lebedev
National Research University of Electronic Technology

Solitons in nonlinear-Schrödinger lattices
Abstract: Nonlinear lattices (NLs) arise nowadays in many physical applications, such as nonlinear optics and models of Bose-Einstein condensates. In the latter case, NLs appear due to periodic modulation of the local nonlinearity strength by means of properly patterned magnetic or optical field. This setting is modeled by the equation of the nonlinear Schrödinger type with a periodically modulated coefficient in front of cubic term. It is known that this model supports simplest (single-peaked, spatially symmetric) solitons. These objects are stable in some interval of the respective chemical potential. In our study we address the following two issues: (i) do there exist more complex solitons in this model, and (ii) if yes, which of them are stable? Addressing the former issue, we have found that the model supports a plethora of complex localized modes, that can be coded by means of bi-infinite words of alphabet with an infinite number of symbols. Addressing the latter issue, we have found that a majority of complex nonlinear modes are unstable. However, there are two stable species: (a) single-peaked fundamental solitons, and (b) a new species of subfundamental solitons, namely, narrow spatially antisymmetric modes, which are squeezed, essentially, into a single NL cell. The stability of these modes is predicted, in a certain region of values of the chemical potential, by a variational approach, and has been checked by means of the linear stability analysis, as well as by direct numerical simulations.

22.01.2016 10:00
Mikhail Rybin
ITMO University

Phase diagram for the transition from photonic crystals to dielectric metamaterials
Abstract: Photonic crystals and dielectric metamaterials represent two different classes of artificial media but are often composed of similar structural elements. The question is how to distinguish these two types of periodic structures when their parameters, such as permittivity and lattice constant, vary continuously. Here we discuss transition between photonic crystals and dielectric metamaterials and introduce the concept of a phase diagram, based on the physics of Mie and Bragg resonances. We show that a periodic photonic structure transforms into a metamaterial when the Mie gap opens up below the lowest Bragg bandgap where the homogenization approach can be justified and the effective permeability becomes negative. Our theoretical approach is confirmed by microwave experiments for a metacrystal composed of tubes filled with heated water. This analysis yields deep insight into the properties of periodic structures, and provides a useful tool for designing different classes of electromagnetic materials with variable parameters.

24.12.2015 10:00
Alexander Uskov
Physical Institute RAS

Excitation of plasmonic nanoantennas with nonresonant and resonant electron tunneling
Abstract: We consider excitation of plasmonic nanoantennas by tunneling electrons, and shows that the quantum efficiency of the excitation is very low (10^-4 - 10^-6) in structures with conventional (nonresonant) tunneling, and can be increased substantially (be several orders!) in structures with Quantum Wells when can take place resonant tunneling.

21.12.2015 14:00
D. Skryabin
Bath University and ITMO University

Solitons and frequency combs in micro-ring resonators
Abstract: Generation of broadband frequency combs in microring resonators provides an attractive tool for many practical applications, where a miniature source of broadband, regularly spaced spectral lines is required. Typical experiments on microresonator combs have been performed with silicon nitride and silica glass rings. Four-wave mixing and soliton formation are the most important building blocks of microresonator combs, which can be linked to the supercontinuum generation in photonic crystal fibers. In this talk I will discuss the influence of Raman scattering and higher order dispersions on solitons and frequency comb generation in silica microring resonators. The Raman effect introduces a threshold value in the resonator quality factor above which the frequency-locked solitons cannot exist, and instead, a rich dynamics characterized by generation of self-frequency-shifting solitons and dispersive waves is observed.

21.12.2015 14:00
Alexander Poddubny
Ioffe Institute and ITMO University

Polariton resonances for ultra-strong coupling cavity optomechanics in multiple quantum wells
Abstract: Polariton-mediated light-sound interaction is investigated through resonant Brillouin scattering experiments in GaAs/AlAs multiple-quantum wells. Photoelastic coupling enhancement at exciton-polariton resonance reaches 10^5 at 30 K as compared to a typical bulk solid room temperature transparency value. When applied to GaAs based cavity optomechanical nanodevices, this result opens the path to huge displacement sensitivities and to novel ultrastrong-coupling cavity phenomena with optomechanical couplings g0 in the range of 100 MHz

18.12.2015 10:00
Dmitriy Krizhanovskii
University of Sheffield

Nonlinear and quantum properties of hybrid light-matter quasiparticles
Abstract: Strongly light-matter coupled systems are interesting from the point of view of both fundamental and applied science. Giant optical nonlinearity of exciton-polaritons can be used in quantum information applications as well as for the development of novel light sources and devices performing fast all-optical signal processing. In my talk I will review the interesting physics of polariton solitons in GaAs- based semiconductor microcavities and waveguides and will present a novel polariton platform based on atom thin van der Waals heterostructures of transition metal dicalcogenides.

18.12.2015 10:00
Oleg Kibis
Novosibirsk State Technical University

Control of the electronic properties of nanostructures by electromagnetic dressing
Abstract: Advances in laser physics and microwave techniques have made possible using a strong high-frequency electromagnetic field as a tool to manipulate the electronic properties of various quantum systems. Since the interaction between electrons and the strong field cannot be described as a perturbation, the system “electron + field”' should be considered as a whole. Such a bound electron-field object, which was called as “electron dressed by field”' (dressed electron), became commonly used model in modern physics. Historically, the modification of electronic properties by the dressing electromagnetic field was studied carefully in atomic and molecular systems. However, advances in nanotechnologies achieved in last decades have made possible to study the dressing-field effects in various nanostructures. The present talk is devoted to the theory of the effects.

09.12.2015 10:00
Oleg Egorov
Friedrich-Schiller-University Jena

Non-equilibrium dynamics of polariton condensates in periodic lattices
Abstract: Last decade there was a remarkable progress in the field of exciton-polaritons which occur inside a high quality semiconductor microcavity due to the strong light-mater coupling. Thanks to extremely small effective masses these composite bosons provide a promising platform for the investigation of the spontaneous formation of coherence in periodic lattices. For instance, spontaneous build-up of both in-phase and anti-phase “super-fluid” states as well as condensation in localized gap soliton states have been observed. This presentation shall provide a review of the nonlinear dynamics of exciton-polaritons in incoherently pumped semiconductor microcavities with embedded periodic lattices. Different regimes of relaxations and oscillatory dynamics are governed by superposition of Bloch eigenstates in such systems. This paves the way for a controlled loading of polaritons into a particular energy state of a band-gap structure enforced by the periodic potential.

30.11.2015 09:30
Nico (C.A.T.) Van Den Berg and Alexander Raaijmakers
University Medical Centre Utrecht

"Modern MRI radio frequency devices" Workshop
Abstract:
Monday, November 30
9.30-11.00 Workshop 1: Basic MRI physics
Larmor frequency; quantum mechanics vs. classical description; precession; NMR; tip angle; rotating frame; T1 and T2 relaxation; Bloch equations; gradient fields; Fourier transform; k-space; gradient echo and spin echo; multi-nuclei.
11.00-11.30 Coffee break
11.30-12.30 Workshop 2: Imaging performance
Spin echo and gradient echo sequences; tradeoff of resolution, scan time and SNR; factors that determine SNR of an MRI experiment; B0 mapping; B1 mapping.
13.30-14.30 Workshop 3: Electromagnetics in MRI
B1+ and B1-, quasistatic approach: law of Biot-Savar; full approach; how to calculate intrinsic SNR from RF simulations; SAR and RF safety.
14.30-15.00 Coffee break
15.00-17.00 Workshop 4: Standard and advanced RF coils in MRI
Body coil; surface receive coils; multi-nuclei coils; receive arrays; transmit arrays; decoupling strategies; dipole antennas; travelling wave.
Tuesday, December 1
9.30-10.30 Workshop 5: Advanced concepts in MRI
Noise; parallel imaging; parallel transmit; multi-nuclei imaging.

16.11.2015 14:00
Paul Urbach
Delft University of Technology

Phase sensitivity in imaging and scatterometry
Abstract: Phase is an important optical parameter that is now increasing being used outside of interferometry. Information about the phase enhances the quality and sensitivity of optical imaging and of the reconstruction of shapes in scatterometry. Phase information can be obtained directly from measurements such as with a Shack-Hartmann or by means of interferometry, or by phase retrieval methods. We will discuss examples from incoherent optical imaging, electron microscopy and surface inspection.

16.11.2015 11:00
Delft University of Technology

Current THz research and Perspective
Abstract: The Terahertz band, large frequency band between the domain of the micro-electronics and the domain of the infrared light has been known for many decades as a gap in the electromagnetic spectrum: difficult to generate, even more difficult to detect. Confined for a long time to astronomers, the area open up to spectroscopist, material science researchers and even reached the domain of homeland security. A great number of scientist have claimed that in the years 2000's Terahertz will emerge as the next big thing. It is now obvious that THz is not yet the mainstream technology that many hoped. Nevertheless, interesting fundamental research is pursued thanks to large improvements in the instruments and the materials such as graphene for example; a dynamic pool of start-up emerged proposing new THz devices for selected applications and more companies investigates the possibilities of the Terahertz equipment in their chain of production for online monitoring. The present talk will give you an overview of the current research in the THz domain, including the one done at TUDelft and its current and possible future applications including those for the communication industry.

09.11.2015 12:00
Bair Damdinov
Buryat State University

Viscoelastic properties of the fluids and their interaction with a solid surface
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

05.11.2015 14:30
Jyrki Saarinen
University of Eastern Finland

Commercializing innovations in photonics
Abstract: Photonics is an enabling technology. Applications are available in, e.g., medical and healthcare; telecommunication, data communication, and data storage; consumer electronics; manufacturing; and diagnostics. In the 21st century, century for photonics, we will see how optics enables virtual reality/augmented reality, ever faster data transmission, foldable display, etc. Commercialization innovation in photonics is an opportunity, but it faces similar challenges as any high-tech product. Besides, optics industry is highly conservative.

05.11.2015 12:30
Jyrki Saarinen
University of Eastern Finland

Future materials and manufacturing for optics
Abstract: Traditional materials for optical components (and their manufacturing methods) are glass (grinding and polishing, molding) and thermoplastics (injection molding). The introduction of ultra-violet (UV) light curable materials, traditionally known as adhesives and glues, have opened novel manufacturing methods for optics, such as roll-to-roll manufacturing by patterning thin layers of UV curable material on top of thin foil, wafer-level optics and 3D printed optics.

15.10.2015 09:45
Kamal Kishor
Технологический университет Дели

Design and characterization of Application Specific Specialty Optical Fibers and Photonic Waveguides
Abstract: An introduction about Photonic Crystal fibers, Metamaterials and Photonic Waveguides and its new design for various new applications for the benefits of the society.

07.10.2015 10:00
Viktoriia Babicheva
ITMO University, University of Georgia

Substrate-mediated zero backscattering from silicon nanoparticle array
Abstract: We study optical properties of all-dielectric metasurfaces on top of the high-index substrate. We show that in contrast to homogeneous environment, where zero backscattering, or Kerker effect, is observed when electric and magnetic moments are in-phase, the blooming of the substrate occurs when the out-of-phase condition is satisfied, i.e. for the wavelength between the resonances of electric and magnetic dipole moments.

07.10.2015 10:00
Dmitriy Zuev
ITMO University

Laser technologies for crystalline silicon photovoltaics
Abstract: Crystalline silicon solar cells are the most widespread type of solar cells in the world. The existing technologies of such solar cells fabrication are completely perfect. Therefore the development of new methods for efficiency increasing of crystalline silicon solar cells is conducted. The present report describes the latest achievements in the laser technologies application for solar cells fabrication and focuses on the investigations in fabrication of «black» silicon surface and transparent conductive oxides for multicrystalline silicon solar cells.

02.10.2015 10:00
Alexander Poddubny
ITMO University, Ioffe Physical Technical Institute RAS

Generation of quantum entangled states in nonlinear plasmonic structures and metamaterials
Abstract: Entangled states underpin many quantum applications including cryptography, logic devices, imaging and sensing. Recent demonstrations of interference between single plasmons reveal the potential for construction of quantum plasmonic circuits, which would further benefit from the integration of quantum sources. We develop a versatile theoretical framework of photon generation through spontaneous wave mixing in arbitrary nonlinear plasmonic and metamaterial nanostructures. Our quantum approach is rigorously based on the electromagnetic Green functions and fully takes into account material absorption and dispersion, providing for the first time accurate predictions of the experimentally measurable photon counts, spatial correlations, and degree of entanglement. We consider specific numerical examples of metallic layer on a nonlinear substrate and nonlinear hyperbolic metamaterial. In these structures, the spontaneous four-wave mixing process leads to generation of entangled plasmon pairs as well as photons entangled with plasmons. We also demonstrate a general one-to-one correspondence between spontaneous parametric downconversion process and sum frequency generation. This allows one to use the current rapid progress in nonlinear metamaterials to optimize structures for entangled photon generation.

02.10.2015 10:00
Mikhail Rybin
ITMO University

Purcell effect and Lamb shift as interference phenomena
Abstract: The Purcell effect and Lamb shift are two well-known physical phenomena which are usually discussed in the context of quantum electrodynamics, with the zero-point vibrations as a driving force of those effects in the quantum approach. Here we discuss the classical counterparts of these quantum effects in photonics, and explain their physics trough interference wave phenomena. As an example, we consider a waveguide in a planar photonic crystal with a side-coupled defect, and demonstrate a perfect agreement between the results obtained on the basis of quantum and classic approaches and reveal their link to the Fano resonance. We find that in such a waveguide-cavity geometry the Purcell effect can modify the lifetime by at last 25 times, and the Lamb shift can exceed 3 half-widths of the cavity spectral line.

25.09.2015 10:00
Konstantin Vytovtov
Oles Honchar Dnipropetrovsk National University

One-dimensional anisotropic photonic crystals: objectives, methods and practical applications
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

21.09.2015 14:00
Dmitry Yudin
ITMO University

Trends in magnonics and their possible photonic counterparts
Abstract: Studying low-dimensional magnetic systems still attracts considerable attention of researchers. In fact, depending on the crystalline symmetry and distance between neighboring spin various magnetic configurations ranging from (anti)ferromagnet states to more complicated textures might emerge. If in addition, inversion symmetry is broken the spins alignment gains a certain chirality due to spin-orbit driven antisymmetric Dzyaloshinskii-Moriya interaction (DM). A certain class of nonlinear equations allow particle-like solution, solitary waves or solitons, which preserve their shape in the duration of their motion and collision processes. There also exists a class of topological solitons whose ground state can not be connected to their excited states and is characterized by some topological number. These particle-like states, e.g. magnetic soliton, skyrmion, domain wall, form a spatially localized clot of magnetic energy. Magnetic skyrmions are chiral spin structures with a whirling configurations so that the plane on which the spins are specified is topologically equivalent to a sphere. Because of that, a certain topological invariant, namely degree of mapping can be ascribed to the structure. The ground state configuration of magnetic structures can be understood by studying corresponding magnetization dynamics, which is based on the solution of phenomenologically derived Landau-Lifshitz equation expressing magnetization precession about effective field. This equation does not take account of dissipation which is physically meaningful and needs to be supplied with the Gilbert term responsible for relaxation. The spin waves are known to be quantized thus leading to the notion of magnons, that can be excited in magnetic materials. In most of spin-wave phenomena a number of magnons is a macroscopic quantity and can be well described by the Landau-Lifshitz equation. As a result, the concept of coherent magnon states analogous to that of quantum optics can be pushed forward. We discuss topologically protected magnetic solitons and skyrmions that might potentially be applied for logical operations and/or information storage in the rapidly advancing field of solitonics (and skyrmionics). The optical analogs will be also considered.

21.09.2015 14:00
Dmitry Gulevich
Loughborough University

Microscopic Tunnelling Model of Josepshon Flux-Flow Oscillator
Abstract: Gulevich talk

08.09.2015 10:00
Andrei Lavrinenko
Technical University of Denmark & ITMO University

Surface waves spectroscopy and effective medium breakdown characterization
Abstract: I will give an overview of our current fabrication and experimental activities in plasmonics and metamaterials at optical frequencies. First I describe fabrication of ultra-thin films of high quality. We particularly focus on uniform gold layers having thicknesses down to 6 nm fabricated by the E-beam deposition on dielectric substrates. Then examples of multilayers with alumina, titania and Cu/Zn alloys deposited by atomic layer deposition and highly-doped InP semiconductors will be given. Experimental activities include effective medium breakdown characterization, directional surface waves spectroscopy by the leakage radiation microscope, absorption enhancement in electroless deposited nanoparticles and observation of nonlinear effects with picosecond pulses propagating in thin gold stripe waveguides.

08.09.2015 10:00
Arseniy Kuznetsov
Agency for Science, Technology and Research, Singapore

Resonant dielectric nanostructures and metasurfaces
Abstract: Resonant nanostructures made of high-refractive index dielectric materials offer a new way for manipulation of light at nanoscale. Due to their inherently high magnetic and electric resonant response and low losses at optical frequencies these nanostructures offers unique functionalities, which are not achievable with conventional nanoscale plasmonics. Simple examples are strong magnetic near-field enhancement and directional scattering by nanoparticles of spherical shape, also known as a Kerker’s effect. At this seminar, I will review this new rapidly developing research direction and present several new results of our team, which demonstrate a huge potential of dielectric nanoantennas for various applications. Fist will be experimental demonstration of highly localized magnetic and electric fields in silicon nanodimer antennas, which can be excited at any polarization of incoming light. Second will show low-loss light propagation in silicon nanoparticle waveguides, which can be much longer than in plasmonic waveguide of similar dimensions. Third will present how the light can be manipulated with almost fully transparent resonant dielectric metasurfaces having a full 2? control over the phase of incoming light at visible and near-IR wavelengths. And finally I will introduce new type of generalized Brewster effect, which can be achieved at dielectric metasurfaces with strong magnetic response.

02.09.2015 10:00
Mikhail Lapine
ITMO University

Recent findings in metamaterial multi-physics.

22.07.2015 10:00
Idelfonso Tafur Monroy
Technical University of Denmark and ITMO University

Photonic Techniques for sub-Terahertz Wireless Data Transmission
Abstract: Wireless data communication links with capacities beyond 100 Gbit/s will require operating at sub-Terahertz frequencies using a large bandpass bandwidth facing new engineering challenges. We review several implementation aspects by using photonic technologies and outline potential direction for further research on device and systems wide aspect to realize Terahertz wireless access systems.

22.07.2015 10:00
ITMO University

Multilayer shells designed by a stochastic optimizer
Abstract: Using stochastic optimizer combined with Mie calculations we provide a route to design multilayer spheres with predefined properties. As an example, we considered two cases. First, we come across some limitations to achieve cloaking effect using dielectric metamaterials and compare obtained designs against previously published results with the use of naturally available dielectric materials; we found that usage of metamaterials leads to a new type of cloaking. Second, we designed highly efficient spherical absorber using realistic material parameters of silver and silicon. It turned out that to achieve the best absorption efficiency for a spherical particle there is no need to tune several multiple resonances using complex multilayer structure; due to dimension effect properly designed spherical particle with only a dipole response is the best one.

02.07.2015 14:00
Boris A. Malomed
Tel Aviv University

Relaxation time mapping of single quantum dots and substrate background fluorescence
Abstract: The concept of the PT symmetry has been intensively investigated in optics on the basis of the paraxial wave equation governing the propagation of light in guiding structures, as this equation is similar to the Schrödinger equation in quantummechanical models, where the PT symmetry was first introduced. In this work, we go beyond the paraxial approximation to demonstrate, solving the full set of the Maxwell's equations for the light propagation in deeply subwavelength waveguides and periodic lattices with balanced gain and loss (in a numerical form), that the PT symmetry may remain unbroken in this setting. Moreover, the PT symmetry in subwavelength guiding structures may be restored after being initially broken with the increase of gain and loss. Critical gain/loss levels, at which the breakup and subsequent restoration of the PT symmetry occur, strongly depend on the underlying guiding structure.

02.07.2015 14:00
Alexandra Sheremet
Russian quantum center

Light interaction with ultracold atoms mediated by a nanofiber
Abstract: Light-matter interaction plays an important role in the implementation of unique application of quantum optics, such as quantum memory protocol. In recent years, the physical implementation of quantum interfaces between light and matter in free space has initiated a very active research. In spite of significant advances, the efficiency of demonstrated quantum memory protocols is not extremely high, which is issued with problems of achievement of high-efficient light-matter coupling. Interfacing guided light with atoms has therefore been foreseen as a promising alternative approach, enabling increase the light-matter coupling as well as obtain a large optical depth. A significant role in such kind of interaction processes belongs to the evanescent field, which appears due to a small diameter of the nanofiber (less then light wavelength) that leads to more effective light-matter coupling in the evanescent field area. In the present work we consider experimental demonstration and theoretical description of the quantum memory protocol for the nanofiber guided light interfacing with 133Cs atoms, cooled in a magneto-optical trap. The nanofiber guided signal field interacts with atoms on atomic transition of D2-line. The control field is applied on resonance to atomic transition and creates the transparency window in accordance with the electromagnetically induced transparency (EIT) mechanism. We consider the light interaction process with all hyperfine atomic structure and discuss the influence of the nanofiber on the light interaction process with the atomic system.

29.06.2015 14:00
Fabian Heisler
ITMO University

Characterization and application of the resonant properties of out-diffused silver nanoislands
Abstract: In this talk I will present the results of the experiments on out-diffused silver nanoisland films. Using the field imprinting technique we were able to obtain separated single nanoislands, giving the opportunity to investigate their resonant properties, using dark-field spectroscopy. Simulations with DDA and COMSOL were compared with the experimental results. The field maps simulated at resonant wavelength for circular islands are shown. After these characterizations the applicability of the nanoisland film as an enhancement substrate for Raman spectroscopy was confirmed by measuring surface enhanced Raman spectroscopy (SERS) spectra of rhodamin 6G and bacteriorhodopsin.

29.06.2015 14:00
Ivan Mukhin
ITMO University

What we can do from the technological point of view.
Abstract: Different technique for plasmon and all-dielectric nanostuctures fabricatoin will be discussed.

19.06.2015 14:00
Leonid Doskolovich
Samara State Aerospace University

Implementation of differential operators with photonic nanostructures
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

19.06.2015 14:00
Eugene Bezus
Samara State Aerospace University

Nanophotonic structures for interference patterns formation, transformation and focusing of surface electromagnetic waves
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

19.06.2015 14:00
Ekaterina Pshenay-Severin
Institute of Applied Physics, Abbe Center of Photonics, Friedrich-Schiller-Universität Jena, Germany

Relaxation time mapping of single quantum dots and substrate background fluorescence
Abstract: We experimentally investigated the role of background signal in time resolved photoluminescence experiments with single quantum dots on substrates. We show that the background fluorescence signal from thin gold films fabricated by electron-beam evaporation and from Al2O3 layers fabricated by atomic layer deposition have to be taken into consideration in experiments on the single photon level. Though all investigated components can be distinguished by their photoluminescence decay rates, the presence of the background signal prevents the observation of photon anti-bunching from single quantum dots. Moreover, a single quantum dot acts as a hot-spot enabling the plasmon supported fluorescence enhancement of gold.

10.06.2015 10:00
Kirill Koshelev
Ioffe Physical Technical Institute RAS, Center for Nanophotonics and Metamaterials

Temperature-tunable semiconductor metamaterial
Abstract: We propose a novel class of temperature-tunable semiconductor metamaterials that exhibit negative refraction in the terahertz spectral range. These metamaterials are based on doped semiconductor superlattices with ultrathin barriers of about 1 nm thickness. Due to the tunnel transparency of the barriers, layers of the superlattice cannot be considered as isolated and, therefore, the classical homogenization approach is inapplicable. We develop a theory of quantum homogenization which is based on the Kubo formula for conductivity. The proposed approach takes into account the wave functions of the carriers, their distribution function and energy spectrum. We show that the components of the dielectric tensor of the semiconductor metamaterial can be efficiently manipulated by external temperature and a topological transition from the dielectric to hyperbolic regime of metamaterial can be observed at room temperature. Using a GaAs/AlGaAs superlattice slab as an example, we provide a numerical simulation of an experiment which shows that the topological transition can be observed in the reflection spectrum from the slab.

10.06.2015 10:00
Ivan Iorsh
Center for Nanophotonics and Metamaterials

2-dimensional hyperbolic medium for electrons and photons based on the array of tunnel-coupled graphene nanoribbons
Abstract: We study the electronic band structure and optical conductivity of an array of tunnel-coupled array of graphene nanoribbons. We show that due to the coupling of electronic edge states for the zigzag nanoribbon structure, the Fermi surface can become a hyperbola similarly to the case of the layered metal-dielectric structures, where the hyperbolic isofrequency contours originate from the coupling of localized surface plasmon polaritons. Moreover, we show that for both types of the ribbon edge, the optical response of the structure can be characterized by a uniaxial conductivity tensor, having principal components of the different signs. Therefore, the tunnel-coupled nanoribbon array can be regarded as a tunable hyperbolic metasurface.

22.05.2015 10:00
Sergey Gupalov
Ioffe Physical Technical Institute RAS

Acoustic oscillations in quantum wires and nanorods of materials with a strong crystalline anisotropy
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

28.04.2015 10:00
Alexey Akimov
Russian Quantum Center, Skolkovo

Towards light-spin interface for NV center in diamond
Abstract: One of key challenges in modern quantum information processing is enabling efficient transfer of quantum information stored in atomic like system onto almost perfect information carriers- photon. Besides quantum information processing and related question of long distance quantum communication efficient quantum interfaces are highly demanded for metrological and sensing applications. There were number of approaches to spin-photon interface proposing use of surface plasmoms, manufacturing structures in diamond, cavities, etc. On another hand recent fast development in the field of metamaterials opened a way to create structures out of hyperbolic metamatherial using CMOS compatible materials. Use on this material a specially in combination with an optical fiber may open a way to create efficient and industry friendly interface for NV centers and, in particular single photon source based on NV. In this work we presenting our efforts on using CMOS compatible hyperbolic metamaterials and optical fibers to construct efficient single photon sources and sensing elements using nitrogen vacancy center in Diamond.

22.04.2015 10:00
Andrey Stashkevich
Université Paris 13

Negative refraction magneto-optical metamaterial based on ultra-thin Co nanowires
Abstract: Our studies of the Brillouin scattering (BLS) from thermal magnons have revealed in arrays of Co nanowires with the diameter below 5 nm in a CeO2 matrix prepared by laser ablation a novel generation of metamaterials characterized by the following original feature. While their overall optical behavior is entirely conventional and thus reliably described by the Maxwell-Garnett approximation, in magneto-optical interactions they behave as negative refraction materials. This is explained by a peculiar quasi-circular polarization of light induced within the wires that has been identified through observation and further theoretical analysis of the reversed Stokes/anti-Stokes (S/AS) scattering asymmetry. In particular, the circular polarization degree has the opposite sign and a much larger absolute value than for the bulk Co film or thick Co wires. This reveals the great potential of seemingly simple wire arrays to manipulate the light at the nanoscale.

22.04.2015 10:00
Aliaksei Dubavik
ITMO University

Functional Colloidal Nanoparticles by Proper Design of Surface and Structure
Abstract: Nanomaterials are cornerstones of nanoscience and nanotechnology. The nature of all nanomaterials is diverse. Nanocrystalline materials are very promising in photonics, optoelectronics, biolabelling and catalysis. In this work we summarized last achievements of the colloidal synthesis and applications of different nanoparticles, among which are semiconductor, metal and metal oxide materials.

17.04.2015 10:00
Alexandra Kalashnikova
Ioffe Physical Technical Institute RAS

Ultrafast laser-induced magnetic dynamics
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

15.04.2015 10:00
Novosibirsk State Technical University

Acoustic-excitonic interaction of indirect dipole exitons in Bose-Einstein condensate
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

10.04.2015 10:00
Germanovich Oleg
CJSC "Konstanta"

Features of electron transfer in multilayer semiconductor nanostructures of different dimensionality
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

07.04.2015 10:00
Kapitanova Polina
ITMO University

Microwave Sources for Optically and Plasmonically Detected Spin Resonance of NV Centers in Nanodimonds
Abstract: The nitrogen-vacancy (NV) center is a point defect in the dimond lattice. It consists of a nearest-neighbor pair of a nitrogen atom, which substitutes for a carbon atom, and a lattice vacancy. Its most explored and useful property is photoluminescense, which can be detected optically or plasmonically from an individual NV center, especially those in the negative charge state (NV−). Electron spins at NV centers, localized at atomic scales, can be manipulated at room temperature by applying a static magnetic field as well as microwave radiation. Here, different designs of microwave sources for NV centers spin manipulation will be presented and discussed.

18.02.2015 10:00
Viktoriia Babicheva
ITMO University

Collective Resonances of Plasmonic Nanoparticle Arrays Excited by Light with Polarization along Lattice Periodicity
Abstract: It is well known that dipole coupling in periodic plasmonic nanoparticle arrays can produce narrow collective resonances at the wavelength corresponding to the Rayleigh anomaly, and spectral sensitivity to the environmental properties of these resonances makes them very attractive for sensing applications. Here we theoretically studied spectral properties of period nanoparticle array in transverse-magnetic polarization. If substrate is present, reflectance and dipole coupling between nanoparticles causes a band of transparency in transmission spectrum.

18.02.2015 10:00
Alexander Atrashchenko
ITMO University

Metamaterials based on Si and A3B5 semiconductors
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

11.02.2015 10:00
Irina L. Livshits
ITMO University

Presentation of International laboratory "Information Technology in optical design and testing"
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

11.02.2015 10:00
M.V. Yakushev
University of Strathclyde, UK

What optical spectroscopy can do to understand materials for thin-film photovoltaics: the chalcopyrites and other semiconductor compounds
Abstract: The chalcopyrite semiconductors based on CuInSe2 are key components in the absorber layer of solar cells which are amongst leading thin-film PV technologies in terms of efficiency and stability. These solar cells have been developed mostly using empirical approaches rather than scientific knowledge-based design: it worked first and was explained later. As a result the progress of the chalcopyrite-based solar cells shows a clear saturation towards not 30%, a theoretical limit for single-junction solar cell, but 21%. The problem seems to be that the materials are too complicated for an empirical design. A solution could be in studying first high structural quality model materials and then using the obtained knowledge for technology grade materials. That is how all other successful semiconductor technologies have been developed. A significant improvement in the quality of the chalcopyrites produced in Strathclyde facilitated the use of fine methods of optical and magneto-optical spectroscopy to study excitonic states and helped to determine a number of fundamental electronic properties. The next step in the development of the chalcopyrites is the substitution of rare and expensive In and Ga with Zn and Sn alternating on the cation sublattice. Transforming chalcopyrite CuInGaSe2 in Cu2ZnSnSe4 with kesterite structure. An encouraging efficiency in excess of 11% has already been reported for solar cells based on this compound. However the material might be far too complicated whereas some other compounds like Cu3BiS3 can probably offer a simpler solution.

05.02.2015 10:00
Sergey Makarov
ITMO University

New laser methods for the creation of element base of nanooptics
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

28.01.2015 10:00
Sergei Kudryashov
The Lebedev Physical Institute of the Russian Academy of Sciences

High-performance femtosecond laser nanofabrication in nanophotonics and plasmonics
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

16.01.2015 10:00
International Laboratory "Mortar chemistry of advanced materials and technologies", ITMO University

Highly porous materials - the basis of modern photovoltaics

22.12.2014 15:00
Alexander Kovrov
ITMO University

Light-trapping in organic solar cells
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

19.12.2014 10:00
ITMO University

Reduction of scattering using thin all-dielectric shells designed by stochastic optimizer
Abstract: Adaptive differential evolution method has been used for optimization of all-dielectric multilayer coatings in order to reduce total scattering from spherical targets. The optimal refractive index profiles have been found for various sizes of targets and thicknesses of coatings. Few profile types that appear to be optimal for various geometrical parameters have been identified. Scattering of the target with diameter of 0.75 wavelength has been reduced by 85% using 0.16 wavelength thick coating formed by isotropic dielectric materials. For larger targets, scattering reduction becomes smaller, but it still reaches 50% for targets with the diameter of 1.5 wavelength. The obtained designs provide a route to implement cloaking without the use of magnetic and anisotropic metamaterials.

19.12.2014 10:00
Kseniia Baryshnikova
ITMO University

Metal coatings and silicon nanoparticles for thin-film photovoltaic systems
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

27.11.2014 11:00
Sergei Tarasenko
Ioffe Physical Technical Institute RAS

Electric and valley photocurrents in graphene
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

24.11.2014 10:00
Maxim Gorlach
ITMO University

Investigation of a strong spatial dispersion regime in discrete dipole structures
Abstract: In this talk I will report our current theoretical results regarding the electromagnetic properties of discrete dipole structures. The basis of our consideration is the discrete dipole approximation and the formalism of dyadic Green function. The main questions that will be discussed in the talk are as follows:
-review of the results related to the nonlocal homogenization theory (on the examples of the discrete dipole structure, wire medium, etc.).
-presentation of the calculated dispersion properties of the structure composed of the uniaxial electric dipoles [Gorlach, Belov. Phys.Rev.B 90, 115136 (2014)]. The discussion of the so-called mixed dispersion regime that corresponds to the strong spatial dispersion in the system.
-current results for the discrete structure composed of the isotropic particles possessing electric polarizability.
-nonlinear nonlocal homogenization theory: theoretical description of second harmonic generation in the discrete dipole structure composed of nonlinear scatterers.

19.11.2014 14:00
Denis Baranov
Moscow Institute of Physics and Technology, All-Russia Research Institute of Automatics

Dielectric nanolaser
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

19.11.2014 14:00
Evgenii Andrianov
Moscow Institute of Physics and Technology

Semiclassical and quantum spaser theory
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

10.11.2014 14:00
Alexander Atrashchenko
ITMO University

Metamaterials based on Si and A3B5 semiconductors
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

31.10.2014 10:00
Rodislav Driben
University of Paderborn (Germany), ITMO Fellowship program

Multidimensional nonlinear modes in BEC condensates with uniform and strongly non-uniform repulsive nonlinearities
Abstract: Families of 3D stable solitons and vortices as well as robust dynamical modes of precession are found in a 3D media with the local strength of the cubic self-repulsion growing from the center to periphery. In addition (3D) stable vortex dipoles of uni-charge as well as completely novel stable dipoles with antipodal topological charges together with hybrid dipoles consisting of 3D solitons and 3D vortices sharing the same vertical axis will be presented in a model with peanut-shaped strong nonlinear traps with uniform and strongly non-uniform nonlinearities.

28.10.2014 16:00
A. Evlukhin
Laser Zentrum Hannover

Optical resonances of silicon nanoparticles
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

24.10.2014 10:00
Fabian Heisler
ITMO University

Characterization of silver nanoisland films using SERS, AFM and dark-field microscopy
Abstract: In this talk I will present the results of several experiments on self-assembled silver nanoisland films. By measuring surface-enhanced Raman spectroscopy (SERS) spectra of rhodamin 6G and bacteriorhodopsin we have shown that these films can serve as SERS substrates.
Using field imprinting technique we have obtained single nanoislands and characterized resonant scattering properties of single particles by means of dark-field microscopy. The AFM measurements allowed us to obtain information about the shape of the respective silver nanoislands.

24.10.2014 10:00
Ivan Sinev
ITMO University

Demonstration of unusual nanoantenna array modes through direct reconstruction of the near-field signal
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

13.10.2014 15:00
Boris O. Scherbin
ITMO University

Development of quantitative approaches on investigation of mechanical characteristics of nano-objects by AFM
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

13.10.2014 15:00
Alexander V. Ankudinov
Ioffe Physical Technical Institute RAS, ITMO University

Near-field optical microscopy of light emitting semiconductor nanostructures using cantilevers
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

07.10.2014 12:00
Maxim Shcherbakov
Laboratory of Nanophotonics and Metamaterials, MSU Physics Department

Enhanced third harmonic generation and nonlinear Fano resonance in the excitation of the Mie resonances in silicon nanodiscs
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

01.10.2014 10:00
V. Milichko
ITMO University

Prospects of research of dielectric nano-and microstructures.
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

22.09.2014 14:00
Dmitri V. Lioubtchenko
Department of Radio Science and Engineering, Aalto University School of Science and Technology, Finland

Passive and active devices based on dielectric rod waveguides for future THz applications
Abstract: The research and development in 0.1-1.0 THz frequency region is extremely significant for wide range of applications, for instance, for wide band telecommunication and imaging systems, material spectroscopy, and medical imaging and treatments. In spite of the problems in technology and high prices for basic components (phase shifters, directional couplers, etc.), the THz systems meet expanding interest of consumers. Dielectric rod waveguides (DRW) are promising transmission lines, when low loss dielectric materials are used, and can be combined with semiconductor devices (oscillators, detectors, mixers, etc.) in the hybrid and/or monolithic integrated circuits. Considerable achievements in this area have been obtained in RAD, Aalto. These developments offer a new opportunity for passive and active component performance, as it allows to decrease the insertion losses. Besides, DRWs have no cut-off frequency enabling broad band operation. Existing materials with controllable parameters are usually very lossy at low THz frequencies, which results in a limitation of the operational frequency. Therefore, carbon nanotubes (CNT) and graphene can be an appropriate solution. We propose to use micro-electromechanical systems (MEMS) in order to produce a novel phase shifter based on an electronically reconfigurable varactor. CNTs and/or graphene are ideally suited as a ﬂexible varactor. Such a phase shifter can be developed by introducing a varactor to the DRW. Both CNTs and graphene components can be integrated into the DRW antenna or to the antenna array surfaces in order to obtain the antenna array for future THz beam steering applications. The applications in communications come from the great interest to the ultra-fast wireless communication links for future wireless systems, providing data rates of more than 10 Gbit/s. However, the output power of semiconductor photomixers is typically only a few microwatts at 1 THz. The efficiency can be greatly increased by using a stack of n-i-pn-i-p superlattice photomixers with extremely small size where ballistic conductivity can be employed. It is well known that the CNTs and graphene have the highest ballistic conductivity. Preliminary experiments show potential of graphene as a photodiode. However, mechanism of photoconductivity is not clear yet. We propose to replace the semiconductor with CNT and/or graphene photodiode. Moreover graphene layer has unique 2-d electron gas properties which allow to build an traveling wave amplifier. Both passive (e.g. phase shifters) and active (DRW with an active layer) components can be integrated into the DRW antenna to obtain a compact transceiver module for THz applications.

18.09.2014 10:00
Kuznetsov S. A.
Novosibirsk State University

Quasi-optical microstructural frequency-selective components in the millimeter and terahertz range: development and application.
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

16.09.2014 14:30
Lysak V.V.
Early Career Fellow, ITMO University

Optical properties of nanostructured semiconductor systems
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

16.09.2014 14:30
Mukhin I.S.
St. Petersburg Academic University, ITMO University

Nanomechanical oscillators
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

12.09.2014 10:00
Alexander I. Chernov
Laboratory of Spectroscopy of nanomaterials, General Physics Institute, Moscow

Formation and optical properties of one-dimensional carbon nanostructures: from single-walled carbon nanotubes with given geometry to graphene nanostrips inside them
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

12.09.2014 10:00
Alexey Yulin
Early Career Fellow, ITMO University

Spatial solitons in media with resonant nonlinearity
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

11.07.2014 10:30
Sergei A. Tretyakov
Aalto University, Finland

"Perfect" absorbers: operational principles and design
Abstract: With recent advances in nanophotonics and nanofabrication, considerable progress has been achieved in realizations of thin composite layers designed for full absorption of incident electromagnetic radiation, from microwaves to the visible. If the layer is structured at a subwavelength scale, thin perfect absorbers are usually called metamaterial absorbers'', because these composite structures are designed to emulate some material responses not reachable with any natural material. We will present a general, conceptual overview of the fundamental mechanisms of full light (or microwave radiation) absorption in thin layers. Possible topologies of perfect metamaterial absorbers are classified based on their fundamental operational principles. For each of the identified classes we provide design equations and give examples of particular realizations.

03.07.2014 10:00
Evgeniy S. Sedov

Nonlinear quantum phenomena in low-dimensional spatially periodic micro-and nanostructures under laser radiation
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

03.07.2014 10:00
Song Mingzhao
ITMO University

Wireless power transfer by using high permitivity ceramic sphere
Abstract: Wireless power transfer(WPT) system can be constructed by using traditional copper helix wire, printed planar loop or other similar structure. In this presentation, we introduce a new type of WPT resonator made of high permitivity ceramic sphere. In this project, WPT is achived via strongly coupled magnetic resonances. Being properly excited, a ceramic sphere can work in different modes. We investigate two basic modes: magnetic dipole mode and magnetic quadrapole mode. As a result, 50% efficiency can be achieved at the distance of 30cm using two ceramic spheres with diameter of 16cm and working frequency of 300MHz.

27.06.2014 11:00
Andrei Lavrinenko
DTU Fotonik, Denmark

Terahertz metamaterials and optical waveguide control
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

23.06.2014 15:00
Richard M. De La Rue
Professor, University of Glasgow

Silicon (oxide), graphene (oxide), metallic and metallo-dielectric nano-photonic structures and devices
Abstract: This presentation will review recent research activity in the areas of silicon photonic micro- and nano-cavity resonators, multi-layer graphene-oxide based photonic devices, arrays of metallic split-ring resonators and metallo-dielectric multi-layer based 'slot' waveguides. Possible applications in bio-medical sensing, environmental sensing and communications will be considered.

03.06.2014 12:00
Ivan Shelykh
Nanyang Technological University, Singapore

Optical analogues of the Aharonov-Bohm effect
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

25.04.2014 10:00
Maxim Gorlach
Belarusian State University

Self-induced torque in anisotropic metamaterial
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

25.04.2014 10:00
Alexey Shcherbakov
Ioffe Physical Technical Institute RAS

Terahertz acoustooptic effects in semiconductor nanostructures
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

16.04.2014 10:00
Andrey Gorbach
University of Bath (UK)

Nonlinear photonics and plasmonics on a surface: graphene as a nonlinear optical material
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

16.04.2014 10:00
Juan Baena

Review of Metamaterial Research at present in Bogota
Abstract: During the last three years, the research on metamaterials in Bogota has been focused on passive metasurfaces design from microwaves to optics. In this talk I will shortly present the following seven ideas developed in this period: 1) Theoretical Constraints on Reflection and Transmission through Metasurfaces; 2) Linear to Circular Polarization Converters Based on Self-Complementary Metasurfaces; 3) Duality for 3D Metamaterial Resonators?; 4) Metasurfaces for Angular Filtering and Beam Scanning; 5) Waveguide Bandpass Filters made of Thick Complementary Small Resonators; 6) Experimental Demonstration of the Saturation of Nanoscaled SRR and CSRR; 7) Plasmonic Complementarity Theorem.

28.03.2014 10:00
Ildar Gabitov
University of Arizona

Parametric interaction of forward and backward waves in metamaterials
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

19.03.2014 10:00
Valentin A. Milichko
IACP FEB RAS

Anomalous optical response of dielectric nanoparticles upon exposure of low-intensity laser fields
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

19.03.2014 10:00
Alexander S. Maloshtan
B.I.Stepanov Institute of Physics, NASB

200 Mbps Real-time True Random Bit Generator Based on Polarization Noise in a VCSEL
Abstract: We report a prototype of real-time physical true random bit generator based on a polarization noise in a vertical-cavity surface-emitting laser (VCSEL) with a bit rate more than 200 Mbps. A comprehensive statistical analysis of bits sequences performed by means of three standard tests of randomness (ENT, Diehard and NIST) shows a high quality of generated random bit sequences.

06.02.2014 10:00
Yuri A. Kumzerov
Ioffe Physical Technical Institute RAS

Nanostructures in porous matrices
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

06.02.2014 10:00
Semen Chervinsky
University of Eastern Finland, Institute of Photonics; St. Petersburg State Technical University, Department of condensed-state physics

Metal nanoisland films: fabrication, plasmon properties, structures
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

03.02.2014 14:00
Dr. Nico van den Berg and Dr. Alexander Raaijmakers
Electromagnetics in MRI group, Ultrahigh Field facility. Imaging Division of the University Medical Center Utrecht, The Netherlands http://www.umcutrecht.nl/subsite/radiotherapy-research/

RF related challenges/opportunities for metamaterials in ultrahigh field MRI
Abstract: Magnetic resonance imaging (MRI) is a medical imaging modality with a strong potential for application of metamaterials as the signal bandwidth is very limited. However, MRI physicists are not experienced in the field of metamaterials and metamaterials researchers are not experienced in the field of MRI. Our visit is aimed at bridging this gap and explore the opportunities that metamaterials can offer to the MR imaging community. In this framework, we will give a presentation that gives a basic introduction into MR physics with focus on its EM principles and presents some of our research on new radiofrequency development in ultra high field MRI. The static magnetic field strength for clinical MRI systems is typically 1.5 and 3 Tesla. In our institute we have an experimental 7 Tesla system available allowing images with higher resolution and image quality. However, the high magnetic field has also introduced severe challenges related to the radiofrequency field required for signal induction. This arises from the increased RF operating frequency (300 MHz) at 7 Tesla causing the RF wavelength in tissue to become smaller than anatomical dimensions. This has made radiofrequency technology an intense and crucial research topic in Ultra high field MRI. New research opportunities arise from the fact that the classical near field coupling used in the MRI community to apply an RF field is suboptimal at these high frequency and antenna arrays are needed to realize optimal penetration of the RF signals into the body. We will present our recent work on the development of RF antenna arrays for MRI of the body at 7 Tesla. Initial images of the heart, kidneys and prostate have a promisingly good image quality. However, since the designs are preliminary, further improvement is expected and metamaterials may well play an important role in optimizing these antenna arrays.

24.01.2014 14:00
Alexander Atrashchenko
Ioffe Physical Technical Institute RAS, University ITMO

Synthesis and investigation of metamaterials based on porous media and semiconductor-metal composites
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

17.01.2014 10:00
Mikhail Petrov
Saint Petersburg Academic University of the Russian Academy of Sciences, University ITMO

Disordered chains of plasmonic nanoparticles
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

17.01.2014 10:00
Andrey Bogdanov
Ioffe Physical Technical Institute RAS, University ITMO

Surface states at the interface between periodic layered metal-dielectric structures and anisotropic conductive layers
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

26.12.2013 16:00
Andrei V. Drozdov
Institute for Analytical Instrumentation RAS

Quasiperiodic dynamics of molecular interactions in water
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

11.12.2013 14:00
Viktoriia Babicheva
DTU Fotonik, Technical University of Denmark

Plasmonic solutions for nanophotonic interconnects and enhancement of photoelectron emission
Abstract: Several planar layouts of plasmonic waveguide modulators that utilize alternative CMOS-compatible materials are proposed. The modulation is efficiently achieved by tuning the carrier concentration in a transparent conducting oxide layer. Alternative designs that utilize field amplification by semiconductor gain materials or ferroelectric domain switch and consequent refractive index change will be presented as well. Collective lattice resonances in plasmonic nanoparticle arrays to enhance photoelectron emission in Schottky-barrier photodetectors and solar cells will be discussed. Finally, if time will allow, the mechanisms responsible for enhanced transmission of electromagnetic wave through an array of subwavelength slits in metallic films will be presented.

11.12.2013 14:00
Ivan Iorsh
University ITMO

Compton scattering in anisotropic metamaterials
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

06.12.2013 10:00
Pavel Melentiev
Institute for Spectroscopy Russian Academy of Sciences, Troitsk, Moscow region, Russia

Giant optical nonlinearity of plasmonic nanostructures
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

06.12.2013 10:00
Sergey Tarapov
O. Ya. Usikov Institute for Radio Physics and Electronics, NAS of Ukraine, Kharkiv

Magnetically active metamaterials for millimeter range in IRE NASU. Experiment
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

26.11.2013 10:00
Lyubov Kozhara
O. Ya. Usikov Institute for Radio Physics and Electronics, NAS of Ukraine, Kharkiv

Experimental study of the microwave properties of the wire lens made of copper conductors at centimeter wavelength range
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

26.11.2013 10:00
Alexei Balmakov
Department of Optics, Gomel State University, Republic of Belarus

Broadband infrared quarter wave plate realized by means of a 3D metal spiral array
Abstract: The ability of helix arrays to filter circularly polarized light efficiently when the light propagates parallel to the helical axis has been demonstrated recently. In this study, we present a broadband linear-to-circular polarization transformer composed of metal micro helices. The device provides significant transformation performance combined with high transmittance over a broad infrared waveband. The high performance was achieved through fine adjustment of a finite-element electromagnetic model. The array design assumes wave propagation perpendicular to the helical axis, which distinguishes it from well studied analogous designs that filter light propagating parallel to the helical axis. To the best of our knowledge, this is the first time this scheme has been realized in the infrared range.

18.11.2013 10:00
Institute of Applied Physics, Friedrich-Schiller-Universität Jena, Germany

Qualitative models in nanophotonics: scientific and educational aspects
Abstract: Recent technological advancements allowing creation of nanoobjects/metamaterials in the optical domain has forced the revisiting of basics electrodynamic principles and assumptions. A large amount of new experimental and theoretical data has to be structured within the framework of a new unified approach, in order to distinguish the really fundamental knowledge from various applications and particular cases. The unified approach appears to be extremely important for educational courses in the area of nanophotonics/optical metamaterials.
In this presentation, various linear and nonlinear effects in area of optical metamaterials will be considered in the frame of a unified approach. Possible application for sensors and telecom will be analysed.
A new concept for theoretical and practical educational courses in area of optical metamaterials will be discussed.

13.11.2013 10:00
Alexey Slobozhanyuk
University ITMO

The use of metamaterials for magnetic resonance imaging
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

13.11.2013 10:00
Veronika Soboleva
Innovative international scientific and educational laboratory "Photon" NR Tomsk Polytechnic University

Types of polarization radiation and their application for diagnostics of charged particle beams
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

08.11.2013 10:00
Ekaterina Pshenay-Severin
Institute of Applied Physics, Abbe Center of Photonics, Friedrich-Schiller-Universität Jena, Germany

Ultra broadband performance measurement of nanostructured metasurfaces
Abstract: The design and creation of two-dimensional nanostructured materials have created a new paradigm in material science: so-called metasurfaces have emerged as a new class of integrated photonic elements featuring only a single or few surface layers composed of subwavelength plasmonic nanostructures. Recently, significant breakthroughs in the wavefront manipulation, such as abnormal and out-of-plane refraction and reflection, have been achieved by laterally inhomogeneous metasurfaces. Another example is the spectrally selective image formation demonstrated by computationally encoded metasurfaces using the principles of digital holography. In the view of the growing structural complexity of contemporary metasurfaces, the lack of comprehensive experimental methods to assess and characterize their building blocks performance becomes a critical issue, hampering development of this field towards real-world applications. Due to restrictions of the state of the art experimental techniques for the phase measurements on metasurfaces, the preference is commonly given to indirect characterization methods relying heavily on rigorous numerical simulations.
In this talk I will demonstrate, based on the Kramers-Kronig transformation analysis, that the use of indirect methods is inadequate for the accurate characterization of complex metasurfaces. In order to provide experimental access to the complex transmission and reflection coefficients of optical metasurfaces and as a prerequisite to assess their broadband performance, we developed an original experimental technique, which I will present in the talk. Additionally, I will demonstrate an experimentally realized compute generated hologram based on metasurfaces, which generates different holographic images at two distinct wavelengths.

08.11.2013 10:00
Tigran A. Vartanyan
Head of laboratory of Surface Photophysics, Center of Information Optical Technologies, NRU ITMO

Optical and electrical properties of self-assembled granular metallic films finding ways to modify them
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

06.11.2013 14:00
Sergei Zhukovsky
DTU Fotonik, Technical University of Denmark

Contrillong spatial plasmon waves in hyperbolic metamaterials
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

06.11.2013 14:00
A.V. Poshakinskiy
Ioffe Physical Technical Institute RAS

Radiative topological states in resonant photonic crystals
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

01.11.2013 15:00
Alexander Chebykin
University ITMO

An overview of ENZ-metamaterials
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

01.11.2013 15:00
Pavel Ginzburg
King’s College London

Nonlinear Nanoplasmonics: Making Use of Metal Non-linearities
Abstract: Nonlinear optics has triggered the evolution of modern optics, yielding discoveries of important phenomena, deep understandings of fundamental optical effects and, moreover, serving as a source for a large variety of applications. Nonlinear optical interactions are relatively weak but can be significantly enhanced using various approaches. Generally, nonlinear optical phenomena are proportional to higher orders of the driving field, motivating the quest for local electromagnetic field enhancement for which various nanostructures have been proven to be beneficial. In particular, noble metals with negative permittivity at optical and infrared wavelengths can support the so-called surface plasmon modes with the deep-subwavelength localization of the electromagnetic energy, overcoming the conventional diffraction limit and leading to the field enhancement effects. Plasmonic nanostructures are perfect candidates for the realization of various concepts for the enhancement of nonlinear effects.
In this talk, we will overview nonlinear plasmonic effects due to intrinsic, hydrodynamic metal nonlinearity, enhanced by sub-wavelength field confinement and interaction between plasmonic resonances. In particular, harmonic generation, solitonic effects and Kerrnonlinearity-induced switching will be discussed. In addition to conventional intensity and phase modulations, active control of light polarization, presenting an important alternative, will be demonstrated.

04.10.2013 15:00
Alexander N. Poddubny
University ITMO, Ioffe Physical Technical Institute RAS

Topological edge states and an analogue of Majorana fermions in the chains of plasmonic particles
Abstract: Topological insulators is a rapidly depeloving field of condensed matter physics. Such systems possess band gap in the bulk and special, so-called topologically protected, edge or surface states. Recently, a significant progress has been made in the study of the topological edge states of photons in various structures. Their specific feature is a robustness against a wide class of external perturbations and disorder.
During this talk a short review will be presented along with new theoretical result: optical analogue of Kitaev's toy model for Majorana fermions in the chains of plasmonic nanoparticles.

04.10.2013 15:00
Roman S. Saveliev
University ITMO

One-Dimensional waveguides of silicon particles with a subwavelength cross-section
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

02.10.2013 10:00
Yuriy Tyshetskiy
School of Physics, University of Sydney, Australia

Unusual physics of exotic media: quantum plasmas and “wire medium” metamaterial
Abstract: In this seminar, I will tell about two media that have interested me recently: quantum plasma, and a “wire medium” metamaterial. What do these two rather different media have in common? They both have interesting, unusual properties, and in both media the spatial dispersion plays an important role.

Quantum plasma
A plasma is regarded as a quantum plasma when the quantum nature of its constituent particles has an appreciable effect on its collective behaviour. Examples of quantum plasmas are the gas of charge carriers in solids (free electrons in metals, electrons and holes in semiconductors), dense matter in the “fast ignition” scenario of inertially confined fusion, the matter in the cores of some dense astrophysical objects.
In this talk, I will discuss some of the interesting features of the well-known “textbook” plasma phenomena that appear in quantum plasmas, as compared to classical plasmas. In particular, I will consider such “elementary” phenomena as plasma shielding of charges, volume and surface wave dispersion and attenuation (including Landau damping), and show how they change, often qualitatively, in quantum plasmas, as compared to these phenomena in classical plasmas.

Guided modes of a wire medium slab
In the second part of the talk, I will tell about a work we recently did jointly with colleagues from the “Metamaterials” lab at NRU ITMO, on guided modes of a wire medium slab. I will briefly show a rather general method for obtaining such modes that can potentially be applied for other, more complex geometries. Then I will show the dispersion structure of the obtained modes, which exhibits strong coupling between slow and fast modes of the same parity, which is only possible due to the nonlocality (spatial dispersion) of the wire medium.

02.10.2013 10:00
Mikhail F. Limonov
Doctor of sciences, Leading Scientist, Ioffe Physical Technical Institute RAS; University ITMO

Fano resonance in photonic crystals and metamaterials
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

26.09.2013 11:00
Purdue University (USA)

Metamaterials: Technology of the Future
Abstract: Manipulating and controlling photons on nanoscale needed for the nanophotonic circuitry and other important applications requires novel plasmonic metamaterials with unique properties. Recent progress in the development of optical metamaterials allows unprecedented control over the flow of light on the nanoscales. Metamaterials (MMs) are rationally designed artificial materials with versatile properties that can be tailored to fit almost any practical need and thus go well beyond what can be obtained with “natural” materials. We review the exciting field of optical metamaterials and discuss the recent progress in developing tunable and active MMs, nanolasers, artificial optical magnetism, semiconductor-based and loss-free negative-index MMs, and a new means for engineering the photonic density of states with MMs. New plasmonic materials with superior properties based on transparent conducting oxides and ceramics will be also discussed. Finally, we review a new approach for controlling light by using meta-surfaces. Similar to the surface science that in the past revolutionized the physics and opened up a family of new phenomena and applications unattainable with 3D systems, we envision that metasurfaces can make a difference for the fields of metamaterials and transformation optics as well as for the science of light in general.

24.09.2013 10:00
Ian F. Akyildiz
Georgia Institute of Technology, USA

Nanonetworks: a new frontier in communications
Abstract: Nanotechnology is enabling the development of devices in a scale ranging from one to a few one hundred nanometers. Nanonetworks, i.e., the interconnection of nano-scale devices, are expected to expand the capabilities of single nano-machines by allowing them to cooperate and share information. Traditional communication technologies are not directly suitable for nanonetworks mainly due to the size and power consumption of existing transmitters, receivers and additional processing components. All these define a new communication paradigm that demands novel solutions. This talk is focused on two research tracks: Electromagnetic Communication and Molecular Communication between nano-scale machines.
In the first part, novel graphene-based plasmonic nano-antennas are presented. Starting from a novel conductivity model of graphene nanoribbons, the propagation of surface plasmons in graphene is characterized. The results reveal that these nano-antennas radiate in the Terahertz Band. Motivated by this result, a novel Terahertz Band channel model is presented, which reveals, among other peculiarities, a huge available bandwidth within the communication range envisioned for nanomachines. Also new communication mechanisms are developed such as femtosecond-long pulse-based modulations and low-weigh coding schemes, energy models and communication protocols.
In the second part, the molecular communication is presented which is a bio-inspired paradigm where the exchange of information is realized through the propagation of molecules. Novel stochastic models of noise sources in diffusion-based molecular communication are presented which reveal the main impairments suffered by the information exchange through this paradigm. Moreover, a closed-form expression of the information capacity is derived through the application of information theory to the molecular diffusion channel. The realization of microbial networks stemming from genetically modified bacteria is finally presented as a potential proof-of-concept for the aforementioned results and as a first possible avenue to future applications.

18.09.2013 11:00
Andrew Gallant
Durham University, UK

THz Plasmonics
Abstract: The field of plasmonics has generated considerable interest in recent years. This talk focuses on the applications of plasmonics in the terahertz region. THz surface plasmon based devices can be constructed using the standard techniques of semiconductor processing technology, as the characteristic length scales are commensurate with the wavelength (i.e. a fraction of a millimetre); and so this task can be easily accomplished. Emerging developments to be discussed include: sensors (including biological sensors); techniques for guiding, concentrating and manipulating THz radiation; and new methods for THz imaging and microscopy.

18.09.2013 11:00
Claudio Balocco
Durham University, UK

Electronic nanodevices for energy harvesting: a novel approach to thermal-energy conversion
Abstract: Every hot object emits a large amount of thermal energy in the form of black-body radiation: the sun, car exhausts, radiator and electronic chips are common examples. However, the energy emitted by low-grade sources at low temperature (200-400 °C) is difficult to convert in useable electricity, and most of it is often wasted. This talk addresses the possibility to harness this energy in the THz and mid-infrared region of the electromagnetic spectrum, using rectennas. A rectenna consists of an integrated broadband antenna to collect radiation, combined with a fast rectifier to convert it to dc power. The rectifiers have to operate at challenging high frequencies (up to 10-30 THz) at room temperature, and recent experimental results based on self-switching nanodiodes will be presented.

11.09.2013 10:00
Pavel Ginzburg
King's College London

Classical and Quantum Nonlocalities in Plasmonics and Metamaterials

05.09.2013 14:10
Andrey Stachkevitch
LSPM, Institut Galilée, Université Paris 13

Ferromagnetic metamaterals
Abstract: This talk is dedicated to metamaterials based on naturally magnetic nano-elements. The concept will be illustrated by two major geometries, namely single films comprised of arrays of ferromagnetic nano-wires of transition metals (Co, Ni) and multi-layer Ni inverse opal structures. The main experimental tool being Brillouin (BLS –Brillouin Light Scattering) spectroscopy, the discussion will include microwave magnetic, magneto-optic and purely optic properties of the above mentioned structures.
The seminar is also intended as an invitation to a discussion concerning the promising possibility of combining the advantages of ”meta-atoms” made of naturally ferromagnetic materials (naturally hyperbolic media) and the properties due to their spatial configuration allowing realization of novel artificial magnetic and dielectric properties (in the spirit of Veselago-Pendry metamaterials).

18.07.2013 10:00
Stanislav B. Glybovskiy
Saint-Petersburg State Polytechnical University

Boundary problem solutions for antennas containing thin-wire meshes
Abstract: Meshes produced by thin metallic wires are widely used in antennas and microwave devices. Such regular two-dimensional structures provide unique electromagnetic properties strongly deepening on mesh parameters. Analysis of the mesh-containing antennas requires novel analytical solutions of many boundary problems. In the present review several solutions are discussed relating to reflector, microstrip and dipole antennas. In all the cases a small inter-wire spacing compared to the wavelength is assumed, which allows using the averaged boundary conditions method. The obtained radiation and matching antenna properties are discussed.

18.07.2013 10:00
Maxim Gorlach
Physics Department of the Belarusian State University (BSU)

Electrical explosion of conductors: the essence of the phenomenon, applications, and approaches to modeling
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

25.06.2013 10:00
Ivan G. Savenko

Quantum kinetic equations of the dynamics of exciton-polariton system in a semiconductor microcavity
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

25.06.2013 10:00
Ksenia Fedorova

Modeling of plasmonic effects in some systems of spectroscopy and photovoltaics
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

20.06.2013 10:00
Elena Semouchkina
Associate Professor, Michigan Technological University; Adjunct Professor, Pennsylvania State University

Microwave Dielectric Metamaterials and beyond
Abstract: Dielectric resonator (DR) arrays operating at microwave frequencies offer a wide range of applications and serve as convenient experimental models for projecting their properties to higher frequencies up to optics. In this talk, I will discuss the problem of providing double negativity in DR arrays; describe different approaches to cloaking using dielectric materials and metamaterials; and present several antenna designs utilizing dielectric properties, including designs of antenna structures for Magnetic Resonance Imaging.

16.06.2013 10:00
Alexander S. Shalin
Candidate of Sciences, Senior research fellow, Ulyanovsk Branch of Kotelnikov Institute of Radio Engineering and Electronics RAS; University ITMO

Optical properties of the highly transparent nanostructured composites, systems with plasmon focusing of radiation and optical forces
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

16.06.2013 10:00
Maxim A. Gorlach
Physics Department of the Belarusian State University (BSU)

Homed rotary moment in an anisotropic medium
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

14.06.2013 10:00
Victor Zalipaev
Krylov Research Centre, St Petersburg; Department of Mathematical Sciences, Loughborough University, UK

Semiclassical analysis of tunneling through a smooth potential barrier and localized states in graphene monolayer with mass gap
Abstract: We present a semiclassical analysis of Dirac electron tunnelling in graphene monolayer with mass gap through a smooth potential barrier in ballistic regime. This 1D scattering problem is formulated in terms of transfer matrix and treated in WKB approximation. For a skew electron incidence this WKB approximation deals with four turning points. Between the first and the second, the third and the fourth turning points two tunnelling domains are observed. Scattering through a smooth barrier in graphene resembles scattering through a double barrier for 1D Schrodinger operator that is 1D Fabry-Perot resonator. The main results of the paper are very simple WKB formulas for the entries of the barrier transfer matrix which explain the mechanism of total transmission through the barrier for some resonance values of energy of a skew incident electron. Moreover, we show an existence of modes localized within the barrier and exponentially decaying away from it and its behaviour depending on mass gap. These are two sets of discrete complex with small imaginary part and real energy eigenlevels determined by Bohr-Sommerfeld quantization condition, above and below the cut-off energy, respectively. It is shown that the total transmission through the barrier takes place when energy of incident electron coincide with a real part of one of complex energy eigen levels. This facts were confirmed by numerical simulations done by the finite element method (COMSOL).

14.06.2013 10:00
Victor Zalipaev
Krylov Research Centre, St Petersburg; Department of Mathematical Sciences, Loughborough University, UK

Electromagnetic guided waves on linear arrays of spheres
Abstract: Guided electromagnetic waves propagating along one-dimensional arrays of dielectric spheres are studied. The quasi-periodic wave field is constructed as a superposition of vector spherical wave functions and then application of the boundary condition on the sphere surfaces leads to an infinite system of real linear algebraic equations. The vanishing of the determinant of the associated infinite matrix provides the condition for surface waves to exist and these are determined numerically after truncation of the infinite system. Dispersion curves are presented for a range of azimuthal modes and the effects of varying the sphere radius and electric permitivity are shown. We also demonstrate that a suitable truncation of the full system is precisely equivalent to the dipole approximation that has been used previously by other authors, in which the incident field on a sphere is approximated by its value at the centre of that sphere.

05.06.2013 10:00
Andrey E. Miroshnichenko
Australian Future Fellow, The Australian National University (Canberra, Australia)

Polarization independent Fano resonance in oligomer-like structures
Abstract: In my talk I will give a brief overview of our recent results on polarization independent optical response of oligomer-like structures for linearly polarized light. Based on the discrete-dipole approximation we have analytically proved that systems with discrete rotational symmetry will exhibit polarization independent extinction, scattering and absorption cross-sections, making then optically isotropic. It is becoming extremely important in the vicinity of the Fano resonances, which makes common description and understanding of this effect in terms of interference of "bright" and "dark" modes questionable. I will also cover some of our results on circular dihroism for oligomer-like structure

05.06.2013 10:00
Robert Donnan
School of Electronic Engineering and Computer Science, Queen Mary University of London, London, UK

A comprehensive error analysis for extraction of complex optical constants by THz-TDS
Abstract: THz Time-Domain Spectrometry (TDS) probes the complex polarization response of materials. Various analytical procedures are applied by many to extract the associated material optical constants. This has commonly been done by iteratively varying material parameters in order to achieve a match between experiment and a theoretical transfer function (TF). Different ways of representing of multiple reflections inside the sample (a Fabry-Perot-like effect) are compared and their contribution to the uncertainty of material parameters is analysed. In addition, this paper offers a basis for data comparison between different THz-TDS systems in transmission mode. Finally, a clear distinction is made between a commonly used basic analysis and an enhanced one, in terms of associated uncertainties in determination of the real and imaginary parts of the complex refractive index.

29.04.2013 10:00
Dmitry S. Kozlov

System of wireless power transmission: principles and techniques to improve the efficiency
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

25.04.2013 14:00
Alexander E. Krasnok
Junior research fellow, University ITMO

Optical antennas based on dielectric nanoparticles
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

22.04.2013 10:00
Igor S. Nefedov
School of Electrical Engineering, Aalto University, Finland

Absorption and thermal radiation in the asymmetric hyperbolic media
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

22.04.2013 10:00
Mikhail E. Guzhva
Candidate of Sciences, Senior research fellow, University ITMO

Nanoantennas for solar cells: Fabrication and first experimental results
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

27.03.2013 11:00
Elizaveta A. Nenasheva
Candidate of Sciences, Senior research fellow, Director of "Keramika" LLC, Chief of SPC of microwave products and high-frequency ceramic materials "NII Girikond"

Ceramic materials and elements for microwave electronics
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

14.03.2013 10:00
Daria O. Ignatyeva
Lomonosov Moscow State University

The propagation of surface plasmon polaritons in layered structures with controlled optical properties
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

14.03.2013 10:00
Ivan Iorsh
Research fellow, University ITMO

Graphene nanophotonics 2013
Abstract: Linear graphene plasmonics
- Basic theory of graphene plasmons.
- Role of damping and spatial dispersion in graphene.
- Plasmons in double layer graphene.
- Graphene tapered waveguide: nanofocusing of THz radiation.
- Graphene nanoantennas/metamaterials hybrid structures.
- Plasmon/optical phonon coupling in graphene.
- Magnetoplasmons in graphene.
- Scattering of graphene plasmons on point and linear defects.
- Plasmons on corrugated graphene sheets.
- Raman scattering in graphene
- Optomechanics in graphene nanocavities
Graphene based photonic devices.
- Graphene based photodetectors.
- Nanotransistors based on graphene
- Graphene based THz antennas
- Far-infrared and THz lasers based on graphene
- Graphene antennas and phased arrays for THz range.
- Chemically functionalized graphene. AC conductor transparent for THz – graphExeter.
Nonlinear graphene plasmonics.
- Thresholdless nonlinear electromagnetic response of graphene – the consequence of carrier linear dispersion
- Optical solitons in graphene
- Cavity quantum electrodynamics with graphene localized plasmons
Exotic applications of graphene.
- Graphene for mode-locking of fiber lasers.
- Hyperbolic metamaterials based on multilayer graphene sheets.
Experimental techniques for the graphene studies.
- Real-space mapping of graphene plasmons by near-field microscopy
Summary and outlook

06.03.2013 11:00
Alexander Krasnok
Junior research fellow, University ITMO

All-dielectric superdirective nanoantennas with the beam steering effect
Abstract: We show a novel way to achieve superdirectivity of optically small nanoantenna. These antennas are an optically small spherical dielectric nanoparticle with a notch in which a point source is located. We explain the effect of superdirectivity by the resonant excitation of high-order multipole modes which are usually negligible for optically small dielectric nanoparticles but become resonant due to the notch. For such an antenna we have revealed a beam steering effect at nanoscale – strongly subwavelength sensitivity of the beam direction to the position of the source phase center. We have confirmed both predicted superdirectivity and beam steering effect experimentally through scaling to microwave frequency range.

21.02.2013 10:00
Alexander Mintairov
Research Professor, EE Department, University of Notre Dame, USA

Near-field optical microscopy of photonic nanostructures
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

15.01.2013 10:00
Internal seminar: Irina Kuchuk, Andrey Krasilin
University ITMO

Opportunities of chemistry department of our laboratory
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

10.01.2013 10:00
Alexander Maloshtan
Laboratory of Quantum Optics, Institute of Physics, National Academy of Sciences of Belarus

Single NV centers in nanostructured diamond and prospects of their use
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

18.12.2012 10:00
I.V. Semchenko, S.A. Hahomov
Educational Institution "Gomel State University Skarina" Belarus

Electromagnetic waves in artificial and natural spiral-structured systems with optimal parameters
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

18.12.2012 10:00
Mikhail Rybin
Senior research fellow, University ITMO

Fano resonance in antennas
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

13.12.2012 10:00
Andrey A. Bogdanov
Ioffe Physical Technical Institute RAS

Electrodynamics of layered semiconductor structures for quantum cascade lasers
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

11.12.2012 10:00
Andrei Andryieuski
Postdoc, DTU Fotonik, Technical University of Denmark

Abstract: Young field of terahertz science and technology experiences need in new materials and devices. Metamaterials based on structured graphene (a one-atom thick material with exceptional physical properties such as high electrical conductivity, optical transparency, tunability by electrochemical potential), provide wide possibilities for terahertz light manipulation. In this talk I will discuss examples of graphene metamaterials applications for terahertz hyperlens and tunable absorber. Moreover, I will give an overview of the research activities in the Metamaterials group at DTU Fotonik, Technical University of Denmark

11.12.2012 10:00
Pavel Ginzburg
Research Fellow, King's College London

Multi-photon processes in nano-plasmonic structures and metamaterials: Classical and Quantum
Abstract: Manipulation of optical near fields in vicinity of quantum sources can significantly improve various tasks, relying on radiation efficiency, polarization, directionality of extracted light, and more. Plasmonic nanostructures and their coupled ordered arrays (metamaterials) are perfect candidates for improvement of both linear and nonlinear effects, and could serve as a platform for various novel concepts. Generally, nonlinear optical phenomena are proportional to higher powers of the driving field, motivating the quest for the local electromagnetic field enhancement and electromagnetic density of states engineering.
Number of intriguing effects, emerging in nano-plasmonic environment will be discussed. Derivation of strong surface nonlinearities in metallic nano-structures will be followed by the demonstration of novel concepts of resonant second-harmonic generation in small metal particles and cascaded second-order plasmon-solitons, propagating along metal films. Plasmonic analogies of quantummechanical effects will be revised with the emphasis on the recent demonstration of plasmonic Hanle effects. Finally, the discussion of electromagnetic field quantization in the presence of dispersive and absorptive bodies will be followed by the demonstration of novel opto-mechanical effect of self-induced force, mediated by metamaterial assembly.

06.12.2012 09:45
Elena Semouchkina
Professor, Department of Electrical and Computer Engineering, Department of Physics, Michigan Technological University, USA; Materials Research Institute, Pennsylvania State University, USA

All-dielectric metamaterials: application perspectives and problems
Abstract: Specific properties of all-dielectric metamaterials and engineered dielectric structures will be discussed in the context of their application for providing negative refraction, energy confinement, antenna miniaturization, and cloaking. Special attention will be paid to coupling, resonance splitting, and metamaterial homogenization problems in cloaking devices. Several dielectric-based cloaking approaches will be outlined. Finally, formation of Fano resonances in all-dielectric metamaterials will be demonstrated and discussed.

06.12.2012 09:45
Sergei A. Tretyakov
Department of Radio Science and Engineering, School of Electrical Engineering, Aalto University, Finland

Zero-scattering and perfect absorption
Abstract: We will discuss extreme properties achievable in scattering from electrically small particles and their arrays, focusing on the conditions for zero scattering, total absorption, and ideal one-way propagation through single-layer arrays of dipoles.

04.12.2012 10:00
Andrey E. Miroshnichenko
Australian Future Fellow, The Australian National University (Canberra, Australia)

Magnetic response of dielectric nanostructures: theory and applications
Abstract: Dielectric nanostructures makes a new twist on light scattering phenomena. Subwavelength particles made of highdielectric materials exhibit very strong magentic response in visible range, which has been recently demonstrated experimentally. The lower losses, compared to plasmonic counterparts, allow to employ dielectric nanostructures for a variety of applications spanning from optical nanotantennas towards metamaterials. In particular, we demonstrated the suppression of the backward scattering and enhancement of the forward scattering due to superposition of the electric and magnetic dipole excitations of a single element. Moreover, due to othognality of optically induced diplole modes, the scattering pattern is polarization independent. It results in azimuthally symmetric unidirectional scattering which can be achieved even for a single element. Furthermore, directionality can be further enhanced by forming a chain of such elements. Although there is a tradeoff between energy confinement and directionality for different inter-particle distances, the properties of vanishing backward scattering and azimuthal symmetry are always preserved even for random ensembles of such elements. It makes them the perfect candidates for compact low loss optical nanoatennas.

04.12.2012 10:00
Mikhail I. Petrov

Electric-field modification of glass and glass-metal nanocomposites
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

23.10.2012 11:30
Igor V. Bychkov
Chelyabinsk State University

Subsystem interaction and dynamic properties of magnetic materials
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

19.10.2012 10:00
Ivan Savenko
Researcher, Science Institute, University of Iceland, Dunhagi-3, IS-107 Reykjavik, Iceland; Division of Physics and Applied Physics, Nanyang Technological University 637371, Singapore

Terahertz source by polaritons and polariton transistor
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

11.10.2012 15:00
Internal seminar: Ivan S. Mukhin, Anton K. Samusev
University ITMO

Manufacturing techniques and methods of study of plasmonic nanostructures
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

04.10.2012 11:30
Andrey Bogdanov
Department of Theoretical Bases of Microelectronics,Ioffe Physical Technical Institute RAS

Tunable metamaterial based on semiconductor superlattices

04.10.2012 11:30
Andrey Zakirov
Graduate student, Moscow Physical-Technical Institute, Dolgoprudnyi

The use of LRnLA algorithms in numerical FDTD simulation

03.10.2012 10:00
David Powell
Research Fellow, Nonlinear Physics Centre, Research School of Physics and Engineering, Australian National University

A modal impedance model of coupled meta-atoms
Abstract: I will start by giving an overview of recent experimental results in microwave metamaterials from the Nonlinear Physics Centre at ANU. This will be followed by a talk on my modal impedance model of coupled meta-atoms. Meta-atoms are the building blocks of metamaterials. It is shown that eigenmodal current distributions are the fundamental degrees of freedom for meta-atoms, and represent a natural basis for describing their excitation and coupling. This approach generalizes simple circuit models to arbitrarily-shaped meta-atoms supporting multiple modes and having highly inhomogeneous current distributions. It is also demonstrated how coupling between metamaterials can be accounted for without the restrictions required by a Lagrangian approach, thus allowing coupling to radiated waves to be included naturally. This approach is strongly inspired by the method of moments approach used to solve electromagnetic scattering problems, but yields a compact analytical model for the dynamics of meta-atoms.

03.10.2012 10:00
Alexander S. Shalin
Candidate of Sciences, Senior research fellow, Ulyanovsk Branch of Kotelnikov Institute of Radio Engineering and Electronics RAS

Nanostructured antireflection coatings and plasmon radiation concentration structures
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

10.07.2012 10:00
Alexander K. Popov
Research Professor of Physics, University of Wisconsin-Stevens Point, USA

Nonlinear Optics with Backward Waves
Abstract: Extraordinary properties of nonlinear optical propagation processes in the metamaterials which enable coherent energy exchange between ordinary and backward waves of different nature are described. These processes include harmonic generation and three- and four-wave frequency mixing that allow optical parametric amplification and frequency conversion of the light waves. Striking contrast with properties of the counterparts in ordinary materials are shown, which results in sharp increase of energy-conversion efficiency. Particularly, exotic features arise in amplification and generation of contra-propagating short pulses. Novel materials, which enable such processes through support of coexisting electromagnetic or vibration (optical phonons) modes, both with positive and negative phase velocities, are proposed. The concepts of unique ultracompact photonic devices, such as data processing chips, tunable nonlinear-optical mirrors, filters, switches and sensors, are discussed.

10.07.2012 10:00
A. A. Bogdanov
Researcher, Ioffe Physical Technical Institute RAS

Effect of anisotropy of conductive layer on the dispersion of electromagnetic waves in a layered metal-dielectric structures
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

29.06.2012 14:00
Boris N. Chichkov
Professor, Hannover Laser Center, Germany

Laser nanotechnology

21.06.2012 10:00
Andrey V. Tyukhtin
Doctor of Sciences, Professor, St. Petersburg State University

Properties of a metamaterial consisting of parallel wires with shell and features of the Cerenkov radiation in such a medium
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

21.06.2012 10:00
Doctor of Sciences, Professor, University of Sydney, Australia, and the Joint Institute for High Temperatures RAS

Surface Plasmon Polaritons in planar dispersive structures: media properties (spatial dispersion and collisions) and the role of multiple boundaries
Abstract: We consider the properties of surface plasmon polaritons (SPPs) in planar dispersive structures, in two particular cases: (1) a semi-bounded degenerate plasma (e.g., a metal), and (2) a heterogeneous structure consisting of a double-negative (DNG) and a single-negative (SNG) metamaterials separated by a dielectric slab.
For case 1, we obtain the dispersion and damping of SPPs, taking into account the spatial dispersion of a metal (due to quantum degeneracy of electrons) and electron-lattice collisions. We show that the spatial dispersion significantly affects the properties of SPPs: the collisionless damping of SPPs (due to spatial dispersion) is comparable to, or dominates over, the purely collisional (Ohmic) damping of SPPs (due to electron-lattice collisions) in a wide range of wavelengths, e.g., from infrared to extreme ultraviolet for SPPs in gold at room temperature. The spatial dispersion is also shown to affect the dispersion of SPPs, especially at short wavelengths (less than the collisionless skin depth, $\lambda\lesssim c/\omega_{p}$).
For case 2, we analyze the dispersion of TM and TE SPPs, accounting for temporal dispersion of the DNG and SNG metamaterials, and ignoring the dissipation and spatial dispersion. We obtain and solve numerically the dispersion equations for TM and TE SPPs for different dielectric slab thickness, obtaining a variety of "fast" and "slow" SPP modes supported by the considered heterogeneous metamaterial structure. In particular, we point out such potentially interesting features as mode splitting for finite slab thickness and regions of negative dispersion. Given the importance of the spatial dispersion for properties of SPPs in a semi-bounded metal (case 1), it would be interesting to also study the effect of spatial dispersion of metamaterials (ignored in case 2) on dispersion and damping of TM and TE SPPs in such structure.

19.06.2012 14:00
Graduate student, Department of Electronics, Oscillations and Waves, SSU

Study of linear and nonlinear waves propagating in one-dimensional photonic and magnonic crystals and at frequencies close to the boundaries of zones of opacity
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

17.05.2012 10:00
Alexey V. Kavokin
Head of the Laboratory of "Spin the device by polaritons", Department of Physics, St. Petersburg State University, Head of Department of Nanophysics and Photonics at the University of Southampton (UK)

Cold exciton gases
Abstract: An indirect exciton is a bound pair of an electron and a hole confined in spatially separated semiconductor layers. Long lifetimes of indirect excitons allow them to cool down to low temperatures below the temperature of quantum degeneracy. This gives an opportunity to study cold exciton gases. We will present spontaneous coherence and condensation, phase singularities, spatial ordering, and polarization textures in a cold excitons gas in the presence of an external magnetic field. We develop a theoretical model accounting for the spin-orbit interaction of electrons and holes, exchange splitting of exciton states and Zeeman effect. This model reproduces the main features of polarization textures observed experimentally and confirms that the polarization textures at low temperature manifest ballistic propagation of cold excitons over the distances exceeding the exciton Bohr radius by 3 orders of magnitude and the exciton thermal De Broglie wavelength by more than an order of magnitude.

26.04.2012 10:00
Ivan V. Iorsh
Research fellow, University ITMO

Metamaterials based on graphene
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

26.04.2012 10:00
Ivan S. Mukhin
St. Petersburg Academic University - Education and Research Center of Nanotechnologies RAS

Metamaterials based on graphene
Abstract: In this presentation, I am going to discuss 2 and 4 terminal suspended graphene devices with clamped and unclamped contact geometry producing be means of laser writer. Some measurement results will be shown as well.

25.04.2012 11:00
Roman S. Saveliev
Engineer, University ITMO

Compensation of losses with gain in multilayer metal-dielectric metamaterials

06.03.2012 15:00
Nikolay R. Gall
Doctor of sciences, Professor, Head of physics of adsorption-desorption processes Lab, Ioffe Physical Technical Institute RAS

Graphene layers on metals: growth, characterization, properties
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

06.03.2012 15:00
Candidate of Sciences, Research fellow, Theoretical Department of the Institute of Spectroscopy RAS (Troitsk)

1) Sloping dark solitons in Bose-Einstein condensates and nonlinear optics, 2) Population dynamics of excitons and free carriers in the quantum wells in hybrid organic / inorganic nanostructures
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

27.02.2012 10:00
Alexander A. Zharov
Doctor of sciences, Leading Scientist, Institute of Physics of Microstructures RAS (Nizhny Novgorod)

On specifics of propagation and scattering of surface plasmons in inhomogeneous metal-dielectric gap nanowaveguides with the local one and two-dimensional narrowings
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

27.02.2012 10:00
Nina A. Zharova
Doctor of sciences, Senior research fellow, Institute of Applied Physics (Nizhny Novgorod)

Electromagnetic cloaking: effect of nonlinearity on the scattering characteristics
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

18.01.2012 10:00
Mikhail I. Petrov

Diffractive structures on the basis of glass-metal nanocomposites: creation and optical properties
Abstract: The report is devoted to the optical properties of glass-nanocomposites - glasses containing metal nanoparticles. Methods for the creation and modification of nanocomposites, as well as the technique for creating diffraction structures based on them are considered. A theoretical analysis of the spectral properties of these structures shows that they demonstrate both the phase and amplitude character, while heavily influenced by the excitation of waveguide and polariton modes in glass-nanocomposites.

11.01.2012 11:00
Dmitry L. Markovich
Student, MIPT

Transparent Metamaterial with Tunable Polarization
Abstract: This report is devoted to the creation of the metamaterial that capable to transform incident linearly polarized plane wave into an elliptically-polarized at 193 THz frequency of telecommunications. Major advantages over conventional polarizers are small size and high transmission power. Basic steps and ideas used in the project, various designs of the material, as well as a brief review articles on related subjects will be presented. Computer simulation was carried out in the CST MW Studio 2009. The report doesn't contain any theoretical material.

28.12.2011 15:00
Роман Киян
Lazer Zentrum Hannover, Nanotechnology Department

Principles of two-photon polymerisation

27.12.2011 15:00
Polina V. Kapitanova
Candidate of Sciences, Research fellow, University ITMO

Controlling split-ring resonators with light
Abstract: We propose a novel approach for creating tunable electromagnetic metamaterials. We demonstrate experimentally that the magnetic resonance of a split-ring resonator (”meta-atom” of the material) with a photodiode operated in photovoltaic mode can be tuned by changing the intensity of an external light source. Moreover, for two coupled resonators we show that we can achieve light induced switching between dark and bright mode response. We investigate metamaterial mirror based on split-ring resonators tunable with light. We show experimentally that it is possible to change the angle of reflected beam by illuminating of inhomogeneous internal light. The beam steering on the order of 10 degrees was achieved when illumination decreasing from left to right was changed to illumination decreasing in opposite direction.

27.12.2011 15:00
Mikhail E. Guzhva
Candidate of Sciences, Senior research fellow, University ITMO

Thermoelectric cooling and thermoelectric generation. Relevance, physical basis, practical applications and ways to improve the efficiency of thermoelectric materials and devices.
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

27.12.2011 15:00
Constantin R. Simovski
Doctor of sciences, Professor, Aalto University (Finland) and University ITMO

Giant radiation heat transfer through micron gaps
Abstract: Near-field heat transfer between two closely spaced media can exceed in orders radiation through the interface of a single black body. This effect is caused by exponentially decaying (evanescent) waves, which form the photon tunnel between two transparent boundaries or boundaries supporting surface waves. However, in the infrared range this huge energy transfer holds only in the case when the gap between two media is as small as a few tens of nanometers. We propose a different paradigm of the radiation heat transfer, which makes possible the strong photon tunneling (and therefore giant radiative heat transfer) for micron-thick gaps. For it the air gap between two media should be modified, so that evanescent waves are transformed inside it into propagating ones. This modification is possible without increasing the phonon thermal conductance between two media. The suggested structure containing arrays of nanotubes or nanowires is designed so that the photovoltaic conversion of the transferred heat will not be altered by these arrays.

14.12.2011 11:00
Dmitry Skryabin
Professor, University of Bath (UK)

Polariton-solitons
Abstract: I'll describe several results by the Bath group and its collaborators on possibility to design systems with stable plasmon-polariton solitons and on the theory and recent experimental observations of the microcavity-polariton solitons

23.11.2011 10:00
Sergei I. Kudryashov
Candidate of Sciences, Senior research fellow, Docent, Lebedev Physical Institute RAS

Nanophotonics of periodic surface nanostructures formation. Photonic crystals based on artificial doped opals.

09.11.2011 10:00
Roman E. Noskov
Candidate of Sciences, Research fellow, University ITMO

Subwavelength plasmonic kinks, solitons and oscillons in arrays of nonlinear metallic nanoparticles
Abstract: Due to a strong enhancement of the field induced by the excitation of surface plasmon polaritons and increased optical nonlinearity, surface plasmons can be employed for realization of a variety of nonlinear optical effects. In particular, several nonlinear optical processes have been demonstrated in plasmonic nanostructures, e.g., optical limiting and self-phase modulation in arrays of structured nanoparticles or second-harmonic generation in nanostructured metal films. In addition, strong geometrical confinement can boost the efficiency of nonlinear optical effects, including the generation of subwavelength solitons in metal-dielectric multilayers and arrays of metal nanowires. The solitons supported by such media result from a balance between tunneling of surface plasmon modes and nonlinear self-trapping.
In our work, we suggest and study a novel class of nonlinear effects in arrays of subwavelength metallic nanoparticles. More specifically, we focus on two fundamental nonlinear phenomena: (i) bistability and (ii) modulational instability. We demonstrate that a bistable nonlinear response of each nanoparticle in the array can lead to the formation of a novel type of nonlinear localized modes---plasmonic kinks, which describe switching waves connecting two different states of polarization of metallic nanoparticles. Such plasmonic kinks are characterized by a subwavelength extent and tunable (changing from zero to a finite value) velocity. Moreover, two slowly moving kinks of the opposite polarity are able to create a stable bound state which can be regarded as a deeply subwavelength dissipative plasmon soliton.
We also analyze modulational instability in such nanostructures, and describe numerically several scenarios of its development. We show that modulational instability can result in the generation of regular periodic or quasi-periodic modulations of the particle polarizations, and reveal that the arrays of nonlinear metallic nanoparticles can support long-lived standing and moving oscillating nonlinear localized modes which can be termed plasmon oscillons, in analogy with localized modes in driven granular materials and Newtonian fluids.

09.11.2011 10:00
Andrey I. Denisyuk
Candidate of Sciences, Docent, University ITMO

Plasmonics under the electron beam
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

13.10.2011 10:00
Vasiliy V. Klimov
Doctor of sciences, Chief research fellow, Lebedev Physical Institute RAS

Spontaneous emission of atoms near nanoparticles of complex shape and composition

13.10.2011 10:00
Constantin R. Simovski
Doctor of sciences, Professor, Aalto University (Finland) and University ITMO

On surface states of indefinite materials

29.09.2011 10:00
Ivan V. Iorsh
Research fellow, University ITMO

Nonlinear surface states on the border of metal - dielectric structures
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

29.09.2011 10:00
Roman S. Saveliev
Engineer, University ITMO

Compensation of losses in metamaterials
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

19.09.2011 10:00
Andrey E. Miroshnichenko
Australian Future Fellow, The Australian National University (Canberra, Australia)

Fano resonances and anomalous light scattering by small particles
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

15.09.2011 10:00
Alexander A. Zharov
Doctor of sciences, Leading Scientist, Institute of Physics of Microstructures RAS (Nizhny Novgorod)

Nonlinear interaction and mutual control of intersecting wave beams
Abstract: We introduce a concept of resonant tunneling photonic nanotriod which makes possible mutual control of cross-cut light flows. The idea of this concept is based upon strong resonant interaction between near phase-matched quasi-localized eigenmodes of nonlinear planar dielectric waveguide and incident beam. We demonstrate that by means of variation of input guided wave intensities even small nonlinear phase mismatches may switch the bistable system from one equilibrium state to another and back that results in deep modulation of beam reflection and transmission coefficients due to the exchange between trapped and free photons. Suggested nano-size device can also serve as light amplifier, light modulator, controlled coupler or light flows divider, etc.

02.09.2011 15:00
Constantin R. Simovski
Doctor of sciences, Professor, Aalto University (Finland) and University ITMO

Design strategy for plasmonic light trapping in thin-film solar cells

28.07.2011 10:00
Pavel Ginzburg
Ph.D., Post doctorate International Newton Fellow and Rothschild Fellow, King's College London

Nano-photonic Devices based on Modified Light-Matter Interactions
Abstract: The nowadays challenges in micro-electronics and photonics are partially directed to increase the speed of devices and reduce their physical dimensions and operation power. Novel materials, light sources, and development of electronics-to-photonics interfaces, can provide solutions for some of the challenges.
We demonstrated both theoretically and experimentally various devices for nano-confinement of IR light along with some of their fundamental focusing limits and new families of plasmonic particles with unique optical properties. In addition, we introduce all-semiconductor tunable low-loss negative-index metamaterials based on coupled quantum wells and dots and quantum-cascade plasmonic sources. As additional type of sources, we investigate a novel process of semiconductor two-photon emission, employed to generation and detection non-classical states of light, and opening new horizons for all-semiconductor room-temperature quantum communication technologies.

28.07.2011 10:00
Ivan I. Shishkin
Junior research fellow, University ITMO

Introduction to laser nanolithography (continued). Works of M. Wegener

11.07.2011 14:00
Alexey P. Slobozhanyuk
Student, University ITMO

Microwave superlens with sloped facets

11.07.2011 14:00
Dmitry S. Filonov
Student, University ITMO

Zharov plasmonic cloak

11.07.2011 14:00
Anna V. Vozianova
Research fellow, University ITMO

The new design carpet cloak

11.07.2011 14:00
Mikhail K. Khodzitskiy
Research fellow, University ITMO

Spiral cloak

06.07.2011 10:00
Ivan I. Shishkin
Junior research fellow, University ITMO

Introduction to laser nanolithography

29.06.2011 10:00
Mikhail F. Limonov
Doctor of sciences, Leading Scientist, Ioffe Physical Technical Institute RAS

Photonic glass and Levy glass - structure, properties and possible applications

06.06.2011 10:00
Junior research fellow, University ITMO

Generation of radiation tripled and combination frequencies in the interaction of counterpropagating light waves of a few oscillations in media with cubic nonlinearity
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

06.06.2011 10:00
A. A. Stashkevich
LSPM CNRS (UPR 3407), Université Paris 13, 93430 Villetaneuse, France

Metamaterials based on ferromagnetic nano-elements: from the effective medium to magnonic behaviour
Abstract: Metamaterials based on nanostructured ferromagnetics are interesting due to the richness of the physics of wave phenomena. They are also considered as potential candidates for a number of important applications, such as microwave signal treatment and magneto-optical light modulation. Magnetic dynamic properties of such systems can be varied over a very wide range by independently modifying the shape and the size of nano-elements, their separation, their chemical composition as well as the nature of the matrix.

06.06.2011 10:00

The interference of the broadening of the emission spectrum due to self-phase modulation and generation of triple frequencies with self-interaction of one-period optical waves
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

05.06.2011 13:00
Stanislav I. Maslovski
Senior research fellow, University ITMO

New devices for formation and transmission of near-field images based on wire media

18.05.2011 11:00
Victor G. Bespalov
Doctor of sciences, Professor, Deputy Head of Department, Senior research fellow, University ITMO

Pulse thermography

18.05.2011 11:00
QE II Fellow, Australian National University (Canberra, Australia)

Nonlinear metamaterials

11.05.2011 10:00
Stanislav I. Maslovski
Senior research fellow, University ITMO

Casimir forces in wire media

11.05.2011 10:00
Mikhail Lapine
PhD (Dr rer. nat.), Research fellow, University ITMO

Nonlinear and tunable metamaterials based on split ring resonators (SRR)

20.04.2011 10:00
Alexander N. Poddubny
Candidate of Sciences, Research fellow, University ITMO

Purcell factor in hyperbolic media
Abstract: Sorry, this entry is only avaiable in Russian. Click to change language.

20.04.2011 10:00
Andrey S. Potemkin
Junior research fellow, University ITMO

Green function for hyperbolic media

29.03.2011 10:00