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Imeni Vladimira Il'icha Lenina, Russia

The Volgograd State Pedagogical University , is one of the major pedagogical institutions in the Russian Federation. The university is located in Volgograd, formerly known as Stalingrad . Wikipedia.


Belonenko M.B.,Volgograd State Pedagogical University | Fedorov E.G.,Volgograd State University of Architecture and Civil Engineering
Optics and Spectroscopy (English translation of Optika i Spektroskopiya) | Year: 2011

We considered the propagation of laser monochromatic radiation in a superlattice that contains regions with an elevated concentration of carriers. The model of the energy spectrum of electrons is chosen in the strong coupling approximation. The electromagnetic field is described quasiclassically with Maxwell equations, which, as applied to the problem under study, are reduced to a non-one-dimensional sine-Gordon wave equation for the vector-potential. We analyzed the wave equation in the approximation of slowly varying amplitudes and phases and obtained and numerically solved an effective equation that describes the electromagnetic field in the superlattice. We studied different regimes of propagation of laser radiation, analyzed diffraction by regions with an elevated electron concentration. © 2011 Pleiades Publishing, Ltd. Source


Belonenko M.B.,Volgograd State Pedagogical University | Fedorov E.G.,Volgograd State University
Optics and Spectroscopy (English translation of Optika i Spektroskopiya) | Year: 2012

The propagation of monochromatic laser radiation in a volume system of quantum dots (QDs) that are tunnel-coupled along one axis is considered. The electron energy spectrum of the QD system is modeled in the tight-binding approximation with allowance for the Coulomb interaction of electrons in the Hubbard model. The electromagnetic field of laser radiation in a QD system is described quasi-classically by Maxwell equations; as applied to this problem, they are reduced to a non-one-dimensional wave equation for the vector potential. As a result of the analysis of the wave equation in the approximation of varying amplitudes and phases, an effective equation describing the electromagnetic field in a QD system is obtained and numerically solved. The influence of the parameters of the system and the amplitude and frequency of the field of incident laser radiation on the character of its propagation is investigated. Nonmonotonic dependences of the factor characterizing the laser beam diffraction spread on the parameters of the electron energy spectrum of the system are obtained. © 2012 Pleiades Publishing, Ltd. Source


Belonenko M.B.,Volgograd State Pedagogical University | Glazov S.Y.,Volgograd State Pedagogical University | Mescheryakova N.E.,Volgograd Business Institute
Semiconductors | Year: 2010

The effect of an ac electric field on the conductance of a system of single-wall semiconductor-type carbon nanotubes placed in a dc electric field is considered. The strength vectors of dc and ac electric fields are directed along the nanotube axis. The electronic system of carbon nanotubes is considered in the context of the Boltzmann kinetic equation in the relaxation-time approximation. The dependence of the current density in the system on the characteristics of applied fields is studied. The effect of absolute negative conductance is detected. © 2010 Pleiades Publishing, Ltd. Source


Kryuchkov S.V.,Volgograd State Pedagogical University | Kuhar E.I.,Volgograd State Pedagogical University
Semiconductors | Year: 2012

The longitudinal current-voltage characteristic of a graphene-based superlattice in high-frequency electric fields, such that the strength of one of the fields oscillates along the superlattice axis and the strength of the other perpendicularly to this axis, is calculated. It is shown that, if there is a transverse high-frequency field only, there exists a possibility for sharply increasing the current density in the negative-differential-conductivity region of the static current-voltage characteristic of the superlattice. The current density exhibits a jump, if the oscillation frequency of the field strength approaches the Bloch oscillation frequency. It is shown that, in such a situation, absorption of an electromagnetic wave in the graphene-based superlattice gives way to amplification. © 2012 Pleiades Publishing, Ltd. Source


Glazov S.Y.,Volgograd State Pedagogical University | Kubrakova E.S.,Volgograd State Pedagogical University
Bulletin of the Russian Academy of Sciences: Physics | Year: 2011

The effect of a constant electric field on plasma waves in a two-dimensional electronic gas in a sys- tem with periodic potential is investigated. A dispersion relation ω(k) is obtained using the high temperature approach. The main and resonant modes of plasma waves are investigated numerically. Regions of one-par- ticle and collective excitations are identified. Calculations are performed on the basis of the plasma wave quantum theory in a random-phase approximation with allowance for the Umklapp processes. © Allerton Press, Inc., 2011. Source

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