The Galerkin method for singularly perturbed boundary value problems on adaptive grids

Voronezh. Translated from Sibirskii Matematicheskii Zhurnal, Vol. 31, No. 5, pp. 138–148, September–October, 1990.     

Dependences of the Transport Scattering Time and Quantum Lifetime on the Two-Dimensional Electron Gas Density in Modulation-Doped Single GaAs Quantum Wells with AlAs/GaAs Short-Period Superlattice Barriers

JETP Letters - The dependences of the transport scattering time τt, quantum lifetime τq, and their ratio τt/τq on the density ne of the electron gas in modulation-doped single...     

Microwave-Induced Magneto-Intersubband Scattering in a Square Lattice of Antidots

JETP Letters - The effect of microwave radiation on low-temperature electron magnetotransport in a square antidot lattice with a period of d ≈ 0.8 µm based on a GaAs quantum well with...     

Nonlinear magnetotransport in a two-dimensional electron system in a square array of antidots in GaAs/AlAs heterostructures

Nonlinear magnetotransport of two-dimensional electrons in square antidot lattices prepared on the basis of selectively doped GaAs/AlAs heterostructures with the period that is much less than the electron mean free path in the initial GaAs quantum wells but is much larger than their Fermi wavelength has been studied. It has been shown that the character of the nonlinear transport of the two-dimensional electrons in the lateral lattices under study changes from classical to quantum with the decrease in the antidot radius. It has been found that the quantum lifetime increases in the magnetic field corresponding to the condition of equality of the cyclotron diameter of two-dimensional electrons and the antidot lattice period.     

X-ray electron probe microanalysis of the reaction zone of thermally stimulated heterovalent anion substitution in the Ga 2III Se 3VI -GaAs solid-phase system

X-ray electron probe microanalysis (EPMA) was used to study the concentration profiles of the main reaction components in the Ga₂Se₃-GaAs heterojunction obtained as a result of thermally stimulated heterovalent anion substitution. It has been found that the quasi-equilibrium and quasi-steady diffusion modes for delivery of chalcogen to the reaction zone are different with respect to the kinetics of the A₂^IIIC₃^VI layer growth. Independent of this, the concentration profiles of the reaction elements are self-organized with time, which allows heterostuctures with a sharp interphase boundary to be reproduced.     

On a modification of the averaging method for seeking higher approximations

Systems in the N.M. Bogolyubov standard form as well as systems with rapid phases are considered. It is proposed to seek the solution in the form of an asymptotic series in a small parameter with coefficients representable in the form of the sum of two functions. The first depends on slow time and is found as the solution of a simpler equation in a finite segment. The second is a trigonometric polynomial of the time (or the angular displacements) with coefficients which depend on the slow time (it is found in an explicit manner). It is convenient to use the results in solving certain problems in celestial mechanics.     

Modulation of Magneto-Intersubband Oscillations in a One-Dimensional Lateral Superlattice

JETP Letters - Low-temperature magnetotransport in a quasi-two-dimensional electron system based on a selectively doped GaAs quantum well with two occupied quantum-confinement subbands with...     

A theorem concerning the existence of periodic solutions of systems of differential equations with delayed arguments

A result is proved concerning the existence of periodic solutions of a system with delay; this theorem is new for ordinary differential equations. An integral operator is constructed, acting in the space of continuous functions, whose fixed points are periodic solutions of the system under consideration.Translated from Matematicheskie Zametki, Vol. 8, No. 2, pp. 229–234, August, 1970.