Science Research Laboratories
Problem Laboratory
NONEQUILIBRIUM PROCESSES IN MATERIALS FOR ELECTRONIC EQUIPMENT
Established on the February 2007
Personal
Currently employed
Supervisor:
Prof. Dr. Sci, Stanislav I. Denisov, senior scientist
Associate Prof. Dr. Taras V. Lyutyy, laboratory head
PhD stud. Yuriy S. Bystrik, junior scientist
PhD stud. Vladislav V. Reva, junior scientist
stud. Bogdan O. Pedchenko, assistant
stud. Anna V. Zayika, assistant
Research areas
1. Driven one-dimensional systems
The theoretical and numerical methods of one-dimensional systems that are excited by regular and stochastic fields are developed. Here we consider the system of particles which are interacting with periodic or random potential and being under the influence of constant or variable force. Such model systems represent a wide range of far from equilibrium physical systems (ion chains Abrikosov vortex, domain walls in magnetics films, etc.) and, therefore, describe properly of their dynamics. Within the framework of the proposed methods we perform the complete statistical description of the dynamics of particles in piecewise linear random potential; introduce a new criterion for stochastic dynamical systems, and, finally, study the chaotic transport of ion chains in asymmetric periodic potentials.
2. Classical and quantum continuous time random walks (CTRW)
The concept of CTRW is utilized for study anomalous diffusion and relaxation systems (particles) that have classic or quantum properties. To this end, the classical model with CTRW summarized in two ways: first, the class distribution functions of waiting time and length of the jumps is complemented by distribution functions of super heavy tails and, secondly, along with infinity 1D walks are considered walk on the surface of the sphere. These generalizations allow, first, to determine the marginal distribution function of particles on the line and classify their modes of super slow diffusion, and second, to describe the slow relaxation in systems, which are exhibiting random rotational dynamics. Finally, work is underway to create a theory of quantum walks, i.e., walks taking place in accordance with the laws of quantum mechanics, with the influence of deterministic and random potentials. It is expected that the nature of the diffusion quantum particles caused by the competition between quantum diffusion acceleration and deceleration because the interaction with potentials.
3. Fine ferromagnetic particles and their ensembles
Here we study the fundamental properties of the ferromagnetic nanoparticle ensembles with a view to their application in fields such as nanoelectronics, bioengineering, nanomedicine and more. The focus is on finding and analyzing the possibilities and benefits of magnetic, thermal and transport effects resulting from non-linear, chaotic or stochastic dynamics of magnetization as nanoparticles, and their rotational motion. These modes arising under action of linearly or circularly polarized magnetic fields, and thermal fluctuations are studied in systems of nanoparticles that are in a solid matrix, viscous fluid and the external periodic potential (nanoparticles under these conditions perspective, for example, to information storage, hyperthermia and targeted drugs delivery, respectively). The influence of dynamic modes, the spatial distribution of the particles and the dipole-dipole interaction on the magnetic susceptibility of ensembles are considered, the resonance phenomena deterministic and stochastic nature are investigated, the terms of most efficient heating of nanoparticles by alternating magnetic field and the conditions of their directional transport in periodic potentials are analyzed. In addition, we study the effects arising from the conductive nanoparticles under the influence of external fields, and also developed and improved techniques of numerical simulation of nanoparticle ensembles using parallel computing technologies.
Scientific Collaborations
Research carried out jointly with famous foreign scientists
- Werner Horsthemke, Department of Chemistry, Southern Methodist University, Dallas, Texas 75275-0314, USA
- Peter Hänggi, Institute of Physics, Augsburg University, D-86135 Augsburg, Germany.
- Holder Kantz, Max Planck Institute for the Physics of Complex Systems, Nothnitzer Str. 38, D-01187 Dresden, Germany.
- Kalliopi Trohidou, Institute of Materials Science, NCSR "Demokritos", 15310 Athens, Greece.
- Chris Binns, University of Lester, University Road, Leicester LE1 7RH, UK.
List of Publications
Research results are published in leading scientific journals
[1] S.I. Denisov, T.V. Lyutyy, B.O. Pedchenko, H.V. Babych. Eddy current effects in the magnetization dynamics of ferromagnetic metal nanoparticles. J. Appl. Phys. 116, 043911 (2014) (Journal impact factor IF=2.185).
[2] V. Méndez, S.I. Denisov, D. Campos, W. Horsthemke. Role of the interpretation of stochastic calculus in systems with cross-correlated Gaussian white noises. Phys. Rev. E 90, 012116 (2014) (IF=2.326).
[3] A.Yu. Polyakov, T.V. Lyutyy, S. Denisov, V.V. Reva, P. Hänggi. Large-scale ferrofluid simulations on graphics processing units. Comput. Phys. Commun. 184, 1483 (2013) (IF=2.407).
[4] S.I. Denisov, Yu.S. Bystrik, H. Kantz. Limiting distributions of continuous-time random walks with superheavy-tailed waiting times. Phys. Rev. E 87, 022117 (2013) (IF=2.326).
[5] S.I. Denisov, S.B. Yuste, Yu.S. Bystrik, H. Kantz, K. Lindenberg. Asymptotic solutions of decoupled continuous-time random walks with superheavy-tailed waiting time and heavy-tailed jump length distributions. Phys. Rev. E 84, 061143 (2011) (IF=2.326).
[6] S.I. Denisov, A.Yu. Polyakov, T.V. Lyutyy. Resonant suppression of thermal stability of the nanoparticle magnetization by a rotating magnetic field. Phys. Rev. B 84, 174410 (2011) (IF=3.664).
[7] S.I. Denisov, H. Kantz. Continuous-time random walk with a superheavy-tailed distribution of waiting times. Phys. Rev. E 83, 041132 (2011) (IF=2.326).
[8] S.I. Denisov, H. Kantz. Probability distribution function for systems driven by superheavy-tailed noise. Eur. Phys. J. B 80, 167 (2011) (IF=1.282).
[9] S.I. Denisov, H. Kantz. Continuous-time random walk theory of superslow diffusion. Europhys. Lett. 92, 30001 (2010) (IF=2.269).
[10] S.I. Denisov, H. Kantz, P. Hänggi. Langevin equation with super-heavy-tailed noise. J. Phys. A: Math. Theor. 43, 285004 (2010) (IF=1.687).
[11] S.I. Denisov, T.V. Lyutyy, C. Binns, P. Hänggi. Phase diagrams for the precession states of the nanoparticle magnetization in a rotating magnetic field. J. Magn. Magn. Mater. 322, 1360 (2010) (IF=2.002).
[12] S.I. Denisov, H. Kantz. Anomalous biased diffusion in a randomly layered medium. Phys. Rev. E 81, 021117 (2010) (IF=2.326).
[13] S.I. Denisov, T.V. Lyutyy, H.V. Babych, B.O. Pedchenko. Contribution of the Magnetic Field of Eddy Currents to the Gilbert Damping Parameter. J. Nano- Electron. Phys. 6 No 2, 02011 (2014).
[14] S.I. Denisov, O.O. Bondar. Generalized Fokker-Planck Equation for the Modified Landau-Lifshitz Equation with Poisson White Noise. J. Nano- Electron. Phys. 5 No 3, 03035 (2013).
[15] T.V. Lyutyy, V.V. Reva, A.Yu. Polyakov. Simulation of Ferrofluids in Confined Domains. J. Nano- Electron. Phys. 4 No 4, 04027 (2012).
[16] A.Yu. Polyakov, T.V. Lyutyy. Stochastic Dynamics of the Nanoparticle Magnetization Driven by a Circularly Polarized Magnetic Field. J. Nano- Electron. Phys. 2 No 4, 100 (2010).
Research Projects
The staff of the laboratory was successfully completed the following research projects
2012-2014: |
Anomalous diffusion and relaxation properties of classical and quantum continuous time random walks, |
2009-2011: |
Forsed and Spontaneous Dynamics of the Uniaxial Nanoparticles Systems. |
2009-2010: |
Effects of Heavy-Tailed Distributions in Confined Levy Flights and Biased Diffusion |
2005-2008: |
The development of new theoretical methods for analysis of driven systems. |
2005-2008: |
The development of new theoretical methods for analysis of driven systems. |
2006-2008: |
The development of analytical methods for studying excited systems. |
2005-2008: |
Self-organised complex-spin magnetic nanostructures. |