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Research topics
Last Update
24.08.2016

Research topics

  1. Kinetics of bimolecular reactions and self-organization in condensed matter;
  2. Theoretical plasma physics;
  3. Nonlinear excitations in condensed medium.

Research topics description

1. KINETICS OF BIMOLECULAR REACTIONS AND SELF-ORGANIZATION

One of the main aims in the first direction is a study of many-particle (cooperative) effects in kinetics of bimolecular reactions in condensed metter, including radiation defects. Most of this research is based on a novel formalism of many-particle densities described in our book [E.A. Kotomin and V.N. Kuzovkov, Modern aspects of diffusion-controlled reactions (Amsterdam, Elsevier, 1996)].

Surface-induced reactions are known to play a very important role in heterogeneous catalysis. We study these reactions with emphasis on such fundamental phenomena pattern formation, reactant self-organization, regular and irregular reactant concentration oscillations as well as chaotic behavior in the case of simple reactions on low-index crystalline surface. We paid a considerable attention to the diffusion problems in heterogeneous media, e.g. composites or heavily irradiated materials.

We work on fundamental problems of theoretical physics, such as Anderson localization at low dimensions for which we suggested recently an exact analytical solution.

Modelling of different types of reactant self-organization in the catalytic surface reaction

2. THEORETICAL PLASMA PHYSICS

We are working on two main topics: (a) Developments of gyrotrons for novel thermonuclear reactors – study of mode competition and stochastic processes in high-power, high-frequency gyrotrons for ITER. Gyrotrons are microwave sources whose operation is based on the stimulated cyclotron radiation of electrons oscillating in a static magnetic field. Gyrotron devices are now able to generate several orders of magnitude as much power at millimeter wavelength as classical microwave tubes, and can operate at frequencies higher than are conveniently available from other types of tubes. Gyrotron oscillators can have a wide application, including technological processes, atmospheric sensing, ozone conservation, artificial ionospheric mirror, extra-high resolution electron spin resonance spectroscopy, nuclear magnetic resonance spectroscopy, new medical technology spectroscopy, etc. However, the main application of powerful gyrotrons is electron cyclotron resonance plasma heating in thermonuclear reactors-tokamaks. (b) A study of stochastization of magnetic fields in plasma as a possible cause of fast reconnection in the frequently interrupted regime of neoclassical tearing modes and in sawtooth crash on ASDEX Upgrade tokamak. An important goal of fusion research with magnetically confined plasmas is to maximize the achievable plasma pressure. In a tokamak, neoclassical tearing modes NTMs, i.e., magnetic islands with poloidal m and toroidal n mode numbers driven unstable by the loss of bootstrap current inside the island, are of major concern as they are considered to be the most severe limitation to the maximum achievable plasma pressure in conventional tokamak scenarios. Such instabilities involve considerably large displacements of the plasma and can be described in the frame of magnetohydrodynamics (MHD).

3. NONLINEAR EXCITATIONS IN CONDENSED MEDIUM

Nonlinear excitations are central that connects properties of macroscopic objects at large with its background constitued of complex microscopic aggregations of atoms.

Application grade properties emerging at this level of complexity and not anticipated on conventional basis are energy and charge transport in advanced complex oxides and its interaction with electromagnetic radiation unavoidable associated with emergence, interactions and decay of of nonlinear excitations - domains, polar regions, excitons and other coherent structures.

Our research is focussed on nonlinear excitations in complex oxides as a key ingredient supporting entirely new properties of technological significance.