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D. L. Kovrizhin

Publications and source records attributed to D. L. Kovrizhin.

23 records · Page 2Linked to original sources
arXiv2009

Exactly Solved Model for an Electronic Mach-Zehnder Interferometer

We study nonequilibrium properties of an electronic Mach-Zehnder interferometer built from integer quantum Hall edge states at filling fraction $ν{=}1$. For a model in which electrons interact only when they are inside the interferometer, we calculate exactly the visibility and phase of Aharonov-Bohm fringes at finite source-drain bias. When interactions are strong, we show that a lobe structure develops in visibility as a function of bias, while the phase of fringes is independent of bias, except near zeros of visibility. Both features match the results of recent experiments [Neder \textit{et al.} Phys. Rev. Lett. \textbf{96}, 016804 (2006)].

cond-mat.mes-hall↗
arXiv2005

Bose-Einstein condensation of magnons in Cs$_{2}$CuCl$_{4}$: a dilute gas limit near the saturation magnetic field

Based on a realistic spin Hamiltonian for a frustrated quasi-two dimensional spin-1/2 antiferromagnet Cs$_{2}$CuCl$_{4}$, a three-dimensional spin ordering in the applied magnetic field $B$ near the saturation value $B_{c}$ is studied within the magnon Bose-Einstein condensation (BEC) scenario. With the use of a hard-core boson formulation of the spin model, a strongly anysotropic magnon dispersion in Cs$_{2}$CuCl$_{4}$ is calculated. In the dilute magnon limit near $B_{c}$, the hard-core boson constraint is resulted in an effective magnon interaction which is treated in the Hartree-Fock approximation. The critical temperature $T_{c}$ is calculated as a function of a magnetic field $B$ and compared with the phase boundary $T_{c}(B) $ experimentally determined in Cs$_{2}$CuCl$_{4}$ [Phys. Rev. Lett. \textbf{95}, 127202 (2005)].

cond-mat.str-el↗
arXiv2002

The anomalous tunneling of Bose-condensate excitations

We discuss the tunneling of phonon excitations across a potential barrier separating two condensate bulks. It is shown that the strong barrier proves to be transparent for the excitations at low energy $ε$. Moreover, the transmission is reduced with increasing $ε$ in contrast to the standard dependence. This anomalous behavior is due to an existence of the quasiresonance interaction. The origin of this interaction is a result of the formation of the special well determined by the density distribution of condensate in the vicinity of a high barrier.

cond-mat.stat-mech↗
arXiv2001

"Cherenkov radiation" of a sound in a Bose-condensed gas

In terms of linearized Gross-Pitaevskii equation we have studied the process of sound emission arises from a supersonic particle motion in a Bose-condensed gas. By analogy with the method used for description of Vavilov-Cherenkov phenomenon, we have found a friction work created by the particle generated condensate polarization. For comparison we have found radiation intensity of excitations. Both methods gives the same result.

cond-mat.stat-mech↗