Manifestation of spin-orbit interaction in tunneling between 2D electron layers

An influence of spin-orbit interaction on the tunneling between two 2D electron layers is considered. Particular attention is addressed to the relation between the contribution of Rashba and Dresselhaus types. It is shown that without scattering of the electrons, the tunneling conductance can either exhibit resonances at certain voltage values or be substantially suppressed over the whole voltage range. The dependence of the conductance on voltage turns out to be very sensitive to the relation between Rashba and Dresselhaus contributions even in the absence of magnetic field. The elastic scattering broadens the resonances in the first case and restores the conductance to a larger magnitude in the latter one. These effects open possibility to determine the parameters of spin-orbit interaction and electrons scattering time in tunneling experiments with no necessity of external magnetic field

Configuration interaction in delta-doped heterostructures

We analyze the tunnel coupling between an impurity state located in a $\delta$-layer and the 2D delocalized states in the quantum well (QW) located at a few nanometers from the $\delta$ -- layer. The problem is formulated in terms of Anderson-Fano model as configuration interaction between the carrier bound state at the impurity and the continuum of delocalized states in the QW. An effect of this interaction on the interband optical transitions in the QW is analyzed. The results are discussed regarding the series of experiments on the GaAs structures with a $\delta$-Mn layer.Comment: arXiv admin note: substantial text overlap with arXiv:1111.089

Effect of intersubband scattering on weak localization in 2D systems

The theory of weak localization is generalized for multilevel 2D systems taking into account intersubband scattering. It is shown that weak intersubband scattering which is negligible in a classical transport, affects strongly the weak-localization correction to conductivity. The anomalous magnetoresistance is calculated in the whole range of classically low magnetic fields. This correction to conductivity is shown to depend strongly on the ratios of occupied level concentrations. It is demonstrated that at relatively low population of the excited subband, it is necessary to use the present theory because the high-field limit asimptotics is shown to be achieved only in classical magnetic fields.Comment: 18 pages, 4 figures. Accepted to Phys. Rev. B 6

Spatial structure of Mn-Mn acceptor pairs in GaAs

The local density of states of Mn-Mn pairs in GaAs is mapped with cross-sectional scanning tunneling microscopy and compared with theoretical calculations based on envelope-function and tight-binding models. These measurements and calculations show that the crosslike shape of the Mn-acceptor wavefunction in GaAs persists even at very short Mn-Mn spatial separations. The resilience of the Mn-acceptor wave-function to high doping levels suggests that ferromagnetism in GaMnAs is strongly influenced by impurity-band formation. The envelope-function and tight-binding models predict similarly anisotropic overlaps of the Mn wave-functions for Mn-Mn pairs. This anisotropy implies differing Curie temperatures for Mn $\delta$-doped layers grown on differently oriented substrates.Comment: 4 pages, 4 figure

Analysis of plasmonic nanoparticles applications and their influence on scattered electric field

It is known that plasmon-induced photocatalytic reaction can may occur due to the excitation of electrons on the surface of plasmonic nanoparticles (NP) but there are also other ways due to which a «hot electron» transfer reaction and a photocatalytic reaction are possible. Nowadays, there are several reports that highlight possible methods of various applications of photocatalytic reactions. The first aim of this report is to analyze excited researches about different mechanisms of photocatalysis and their implications in medicine to find out new approach in cancer treatment available for every person in society, and diagnostics. The second aim is to show nanosphere 3D simulation results of enhancement and electric field dependents of irradiation light wavelength, and size of NP. Also, this review is highlighting some investigation methods of plasmon-induced photocatalytic reaction at the micro and nanoscal