Maxwell relaxation of excitons in double quantum wells

The spreading of dipolar excitons in double quantum wells is described by a nonlinear continuity equation. It has been shown that the law of corresponding states holds, which allows one to find the dependence of the characteristic process parameters on the amplitude and width of the initial distribution. In contrast to usual (linear) diffusion, the spreading occurs much faster in the one-dimensional case than in the two-dimensional case.     

Inelastic light scattering by dipolar excitons

The cross section for inelastic light scattering by a system of spatially indirect excitons is calculated. It is shown that there are two resonant scattering channels, one related to the transitions via the vacuum and the other via the two-exciton states of the crystal, and their contributions to the scattering amplitude cancel each other. As a result, there is no resonance enhancement of light scattering by excitons for photon energies in the vicinity of the band gap.     

Spin-dependent localization of electrons in low-dimensional systems

Possibilities of spatial localization of spin-polarized electrons due to spin–orbit interaction are investigated theoretically. Situations most interesting for us are the ones where electrons of one spin state (helicity) are localized while the opposite helicity relates to extended wave functions. On examples of simplest short range potentials it is shown that such spin separation is, in principle, possible. Magnetic properties of electrons bound to a shallow 2D axially symmetric well are considered. Accounting for the spin–orbit contribution results in an anomalously large effective g-factor of this system.     

Edge magneto-exitons (ring excitons) in antidots

Il Nuovo Cimento D - An opening (antidot) in two-dimensional (2D) electron gas placed in a strong perpendicular magnetic field makes it possible the formation of ring-shaped excitons stemming from...     

Polaron Shift of the Levels of a Quantum Wire in a Hybrid Structure with a Bose—Einstein Condensate

JETP Letters - The wavefunction of the transverse motion of electrons in a quantum wire located near a two-dimensional layer of dipole excitons is perturbed by fluctuations of the exciton density...     

Electronic Spectrum and Optical Properties of Quantum Wires Made from Transition Metal Dichalcogenides

JETP Letters - The energy spectrum and optical absorption in a quantum wire of monolayer transition metal dichalcogenides in the shape of a straight strip are investigated theoretically. It is...     

Interaction, damping and possible amplification of 2D plasmons in asymmetric bilayer structures

It is shown that the asymmetry of a double quantum well structure considerably affects the dispersion relations for the optical and intersubband plasmons. A specific mechanism of the plasmon damping arises due to a resonance of the plasmon energy and that of single-particle intersubband transitions. If the population of the subbands is inverted, an amplification of the plasma waves becomes possible.     

Spin-magnetoplasma waves in a 2D electron system

Oscillations of a 2D electron plasma in a transverse magnetic field have been theoretically studied taking into account spin-orbit interaction. Four branches of spin-plasmon oscillations associated with different selection rules for spin and orbital quantum numbers have been shown to appear at a small plasmon momentum in a semiclassical limit (the Fermi energy is much higher than the Landau quantum). In the quantum case (the filling factor ν is about unity), the number of branches changes from three to six depending on ν value.     

Composite particles in quantum wells

Bound states of composite particles in single and double quantum wells are studied. The spectrum and polarizability of an indirect trion and an indirect D ^? center (a negatively charged donor) in crossed electric and magnetic fields are found. Bound dielectron states in a single quantum well are studied. The possibility of observing a dielectron experimentally by the magnetic-dipole absorption of electromagnetic waves is pointed out.     

Screening of static perturbation in a system of dipole excitons

The screening of local electrostatic perturbation by indirect excitons has been investigated. It has been shown that the linear screening is dielectric, and the effective dielectric constant may be large in the case of high degeneracy of the Bose gas of excitons. The emergence of a condensate significantly changes the behavior of the perturbation potential at infinity, leading to power-law asymptotic behavior with large exponents. In the nonlinear regime, the screened potential is saturated with an unlimited increase in the initial perturbation.