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A. D. Chepelianskii

Publications and source records attributed to A. D. Chepelianskii.

45 records · Page 3Linked to original sources

Hall detection of time-reversal symmetry breaking under AC electric driv ing

In a four terminal sample microscopic time-reversibility leads to symmetry relations between resistance measurements where the role of current and voltage leads are exchanged. These reciprocity relations are a manifestation of general Onsager-Casimir symmetries in equilibrium systems. We investigate experimentally the validity of time reversal symmetry in a $GaAs/Ga_{1-x}Al_xAs$ Hall bar irradiated by an external AC field, at zero magnetic field. For inhomogeneous AC fields we find strong deviations from reciprocity relations and show that their origin can be understood from the the billiard model of a Hall junction. Under homogeneous irradiation the symmetry is more robust, indicating that time-reversal symmetry is preserved.

cond-mat.mes-hall↗

Ratchet transport of interacting particles

We study analytically and numerically the ratchet transport of interacting particles induced by a monochromatic driving in asymmetric two-dimensional structures. The ratchet flow is preserved in the limit of strong interactions and can become even stronger compared to the non-interacting case. The developed kinetic theory gives a good description of these two limiting regimes. The numerical data show emergence of turbulence in the ratchet flow under certain conditions.

cond-mat.stat-mech↗

Synchnonization, zero-resistance states and rotating Wigner crystal

We show that rotational angles of electrons moving in two dimensions (2D) in a perpendicular magnetic field can be synchronized by an external microwave field which frequency is close to the Larmor frequency. The synchronization eliminates collisions between electrons and thus creates a regime with zero diffusion corresponding to the zero-resistance states observed in experiments with high mobility 2D electron gas (2DEG). For long range Coulomb interactions electrons form a rotating hexagonal Wigner crystal. Possible relevance of this effect for planetary rings is discussed.

cond-mat.mes-hall↗

Photogalvanic current in artificial asymmetric nanostructures

We develop a theoretic description of the photogalvanic current induced by a high frequency radiation in asymmetric nanostructures and show that it describes well the results of numerical simulations. Our studies allow to understand the origin of the electronic ratchet transport in such systems and show that they can be used for creation of new types of detectors operating at room temperature in a terahertz radiation range.

cond-mat.mes-hall↗

Magnetization of ballistic quantum dots induced by a linear-polarized microwave field

On a basis of extensive analytical and numerical studies we show that a linear-polarized microwave field creates a stationary magnetization in mesoscopic ballistic quantum dots with two-dimensional electron gas being at a thermal equilibrium. The magnetization is proportional to a number of electrons in a dot and to a microwave power. Microwave fields of moderate strength create in a one dot of few micron size a magnetization which is by few orders of magnitude larger than a magnetization produced by persistent currents. The effect is weakly dependent on temperature and can be observed with existing experimental techniques. The parallels between this effect and ratchets in asymmetric nanostructures are also discussed.

cond-mat.mes-hall↗

Directed transport born from chaos in asymmetric antidot structures

It is shown that a polarized microwave radiation creates directed transport in an asymmetric antidot superlattice in a two dimensional electron gas. A numerical method is developed that allows to establish the dependence of this ratchet effect on several parameters relevant for real experimental studies. It is applied to the concrete case of a semidisk Galton board where the electron dynamics is chaotic in the absence of microwave driving. The obtained results show that high currents can be reached at a relatively low microwave power. This effect opens new possibilities for microwave control of transport in asymmetric superlattices.

cond-mat.mes-hall↗

Directing transport by polarized radiation in presence of chaos and dissipation

We study numerically the dynamics of particles on the Galton board of semi-disk scatters in presence of monochromatic radiation and dissipation. It is shown that under certain conditions the radiation leads to appearance of directed transport linked to an underlining strange attractor. The direction of transport can be efficiently changed by radiation polarization. The experimental realization of this effect in asymmetric antidot superlattices is discussed.

cond-mat.mes-hall↗

Schrodinger cat animated on a quantum computer

We present a quantum algorithm which allows to simulate chaos-assisted tunneling in deep semiclassical regime on existing quantum computers. This opens new possibilities for investigation of macroscopic quantum tunneling and realization of semiclassical Schrödinger cat oscillations. Our numerical studies determine the decoherence rate induced by noisy gates for these oscillations and propose a suitable parameter regime for their experimental implementation.

quant-ph↗

Dynamical turbulent flow on the Galton board with friction

We study numerically and analytically the dynamics of particles on the Galton board, a regular lattice of disc scatters, in the presence of a constant external force and friction. It is shown that under certain conditions friction leads to the appearance of a strange chaotic attractor in an initially conservative Hamiltonian system. In this regime the particle flow becomes turbulent and its average velocity depends in nontrivial manner on friction and other system parameters. We discuss the applications of these results to the transport properties of suspended particles in a laminar viscous flow streaming through scatters.

cond-mat↗