Research Topics

Spintronics

Prof. Yuriy Tver'yanovich, e-mail: yu.tver.At.home.rclph.spbu.ru

The main aim is the development of new materials, which are able to change magnetic properties under laser illumination. It means that a paramagnetic material become ferromagnetic due to laser illumination. It is the result of generation of free carriers with long lifetime. This phenomenon can be used for the light-government by different magnetooptic, spintronioc devices and for recording of information. The research within the frame of the project includes:
1) creation of nano-crystals and thin films of ferromagnetic semiconductors for spintronics;
2) laser-induced change of magnetic properties of semiconductors;
3) investigation of the influence of the magnetic field on the electrical properties of semiconductors.

Localized Laser-induced metal deposition for microelectronics

Dr. Alina Manshina, e-mail: malina.At.home.rclph.spbu.ru

The project is focused on creation of the micrometer size metal structures and elements on the surfaces of dielectrics and semiconductors by the Laser-induced chemical liquid-phase deposition (LCLD). The suggested method allows high adhesive deposition of different metals (Cu, Ni, Au, et al.) on several kinds of substrates including oxide glasses and polymers. The main aim of the project is optimization of the deposition parameters for the minimization of the resistance of deposits, what is of great importance for the microelectronic industry.

Solar cells

Dr. Andrey Tverjanovich, e-mail: andr.At.at1186.spb.edu

Chemical compositions of the system Cu2Se-In2Se3 can be used for production of solar-cells with extremely high efficiency. Thus, it is important to extent the following two technologies for production not only CuInSe2 compound, but also other compounds from this system.
UV laser deposition of the orientated crystalline thin films of the semiconductors for the solar cells with n- and p-type conductivity.
The microwave synthesis of nano-crystals of CuInSe2 for the solar cells.

Microwave synthesis

Dr. Andrey Tverjanovich, e-mail: andr.At.at1186.spb.edu

This method is technologically-appropriate because it can be arranged as continuous chemical process. It does not need vacuum conditions, in extremely temperature or pressure. The development of this method is need in understanding its chemical mechanism, in understanding the peculiarity of inducing different chemical reactions by micro-wave irradiation. It is very important also to develop the using of nano-crystalline materials (synthesized by this method) and to research its properties. The development of the microwave-assisted method of the synthesis of ternary and binary nano-crystalline semiconductors.

Laser writing

Dr. Alina Manshina, e-mail: malina.At.home.rclph.spbu.ru

Laser writing is an extremely efficient method allowing creation of the optical devices with 2D and 3D architecture what is critical for several emerging technologies, including photonics, integrated optics, microfluidics, microelectromechanical systems, and biomaterials. Laser writing is based on laser-induced modification of the structure of the optical materials what results in the optical parameters change in the laser affected region. The aim of the project is the study of the materials liability to laser radiation and achievement of the considerable change of the refractive index in the laser affected zone. It will allow creation of high density 3D optical data storage, efficient elements of integrated optics (waveguides, amplifiers, gratings and so on). Within the frame of the project 2D and 3D structures will be created in thin films and bulk optical materials (mainly chalcogenide glasses) with UV and fs laser radiation. There are some steps in this way: 1) sample preparation (thin film or bulk material), 2) creation of a spatial variation of optical parameters, 3) realization of functional properties.

UV laser deposition

Dr. Evgeniy Borisov, e-mail: borisov.At.home.rclph.spbu.ru

Integrated optics provide a considerable progress in telecommunications as it allows decreasing size and cost of such networks, since some functional optical devices can be combined on a single substrate. Such elements of integrated optics are realized as a planar structure with embedded optical circuits. Silicon and silica glasses, being inexpensive and characterized in detail over a long time, are of widely use as host materials for telecommunication systems and integrated optical devices. However, there are some fundamental limitations, which restrict further improvement of silicon-based elements for fiber-optic networks. Novel optical materials can provide increasing of efficiency and functionality of these devices in future. That is why the project is aimed to creation of integrated optical elements on a base of novel materials: chalcogenide glasses and crystals LiNbO3 and LiNbO3:Fe. Thin films on a base of the named materials will be created with Ultra violet (UV) laser ablation. It is a feasible method for deposition of the films with complicated chemical composition. It allows obtaining homogeneous films, composition of which shows good conformity with composition of a bulk target. The project supposes:
Creation of the thin films with the complex chemical composition and multilayer thin films (with the layer thickness about 10 nm).
Creation of the thin crystalline films of LiNbO3 and LiNbO3:Fe.
Characterization of the deposited films.

Bulk mono-crystals

Dr. Oleg Grunskiy, e-mail: grunsky.At.home.rclph.spbu.ru

Growth of the optical mono-crystals (LiNbO3 with stoichiometric and congruent composition, PbMoO4 and PbWO4, PbMoxW1-xO4) for SAW wafers, acousto- and electro-optics, SHG, holography, parametric light amplification, acousto-optic and fast acting scintillators.

Solid state ionic Nano-ionic

Prof. Yuriy Tver'yanovich, e-mail: yu.tver.At.home.rclph.spbu.ru

It is well known that ion conductivity significantly increases at inter-phase border. The systematic investigation of this phenomenon gives us possibility to produce very effective ion-conductive materials for electrical batteries. The appropriate method of such materials creation is the preparation of multilayer thin films using laser ablation. Every film consists from a lot of thin layers with different chemical composition and some nano-meters in thickness. So, it gives us possibility to produce a meta-material which is the inter-phase border as a whole. Within the project it is planned the investigation of the interphase ionic conductivity of the nano-layered thin films prepared by UV laser deposition.

Atom and quantum optics

Dr. Denis Ivanov, e-mail: ivanov-den.At.yandex.ru

New methods to cool atoms and molecules. Control of ultracold trapped gases via feedback. Numerical analysis of atom-field interaction problems using quantum trajectories. New optical elements for focusing of atomic beams. Diffraction of atoms on from a standing wave.

Supercontinuum generation on a base of photonic crystal fibers

Alexandr Shimko, shimko.At.home.rclph.spbu.ru

Modern fs lasers have opened a new class of phenomena which are based on nonlinear effects resulted from propagation of ultrashort laser radiation through optical fibers. Laser-matter interaction in this case leads to considerable broadening of spectra of the propagated radiation. This effect is called supercontinuum or white light generation. The significant progress in this direction has been achieved with the invention of the photonic crystal fibers (PCF) or holey fibers (HFs). The PCFs consist of a central region (core) surrounded by periodic air holes along its length. Changing of the photonic crystal fibers geometry (air hole spacing and air hole diameter) allows considerable modification of their dispersion properties, what together with the high localization of the radiation in the core permits drastic increase of the nonlinear interaction efficiency. White light generation phenomenon is of great importance for nonlinear optics, optics of ultrashort pulses and pulse-phase modulation, high-precision metrology and so on.