arXiv subjects

N. V. Khotkevych

Publications and source records attributed to N. V. Khotkevych.

3 recordsLinked to original sources

arXiv2016

Quantum interference patterns around magnetic impurities in a 2D electron gas with strong Rashba spin-orbit interaction

Explicit dependencies of the local density of states and the magnetization local density of states have been obtained around magnetic point defects in a two-dimensional electron gas with Rashba spin-orbit interaction . The expressions are given in the Born approximation for arbitrary magnitude and orientation of the defect magnetic moment, and for arbitrary size of the constant of spin-orbit interaction alpha/. On the basis of our asymptotically exact formulas a procedure for the determination of the constant alpha/ in STM experiments is proposed. The novel analytical results are compared with the numerical and approximate results of previous work. At variance with earlier work we find that that magnetic scattering in the presence of spin-orbit interaction does not modify the local density of states and that the spin texture resulting from in-plain orientation of the defect magnetic moment, and elastic scattering, is not a purely in-plane spin texture.

cond-mat.mes-hall↗

arXiv2012

Conductance of a STM contact on the surface of a thin film

The conductance of a contact, having a radius smaller than the Fermi wave length, on the surface of a thin metal film is investigated theoretically. It is shown that quantization of the electron energy spectrum in the film leads to a step-like dependence of differential conductance G(V) as a function of applied bias eV. The distance between neighboring steps in eV equals the energy level spacing due to size quantization. We demonstrate that a study of G(V) for both signs of the voltage maps the spectrum of energy levels above and below Fermi surface in scanning tunneling experiments.

cond-mat.mes-hall↗

arXiv2010

Quantum interference effects in a system of two tunnel point-contacts in the presence of single scatterer: simulation of a double-tip STM experiment

The conductance of systems containing two tunnel point-contacts and a single subsurface scatterer is investigated theoretically. The problem is solved in the approximation of s-wave scattering giving analytical expressions for the wave functions and for the conductance of the system. Conductance oscillations resulting from the interference of electron waves passing through different contacts and their interference with the waves scattered by the defect are analyzed. The prospect for determining the depth of the impurity below the metal surface by using the dependence of the conductance as a function of the distance between the contacts is discussed. It is shown that the application of an external magnetic field results in Aharonov-Bohm type oscillations in the conductance, the period of which allows detection of the depth of the defect in a double tip STM experiment.

cond-mat.mes-hall↗