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.     

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.     

Two-dimensional plasmons in multi-layered structures

The plasma waves and coupled plasmon-acoustic waves due to piezoelectrical effect in superlattices are investigated theoretically. The dispersion relations are obtained, and it is shown that under certain conditions the group velocity of the waves can be extremely small.     

Spin-plasmon oscillations of the two-dimensional electron gas

Interaction of the spins of 2D electrons with an alternating electric field in the plane of the system is considered. It is assumed that the double spin degeneracy is eliminated by the spin-orbit splitting. It is shown that transitions between different spin states produce a narrow absorption band in the degenerate electron gas. In the frequency domain corresponding to these transitions, those frequencies are combined with two-dimensional plasmons; as a result, the plasmon spectrum is modified, and a new type of oscillations occurs, namely, a spin-plasmon polariton. The dispersion law of these oscillations is derived. The problem of the excitation of spin-plasmon polaritons by an external electromagnetic field is solved.     

Coulomb Center in a Transition Metal Dichalcogenide Monolayer

JETP Letters - Electronic processes involving a charged impurity in a transition metal dichalcogenide monolayer and in gapped graphene have been theoretically studied. The spectrum of bound states,...     

Raman Scattering by Plasma Oscillations in Quantum Rings

Resonant Raman scattering in quantum rings with a sufficiently large number of conduction electrons has been studied. The cross section for Raman scattering accompanied by the excitation of a one-dimensional plasmon in a ring has been determined in the self-consistent field approximation.     

Bose–Einstei condensation of dipolar excitons in a ring trap

The temperature of Bose–Einstein condensation and the fraction of particles in a condensate for a system of spatially indirect dipole excitons in an electrostatic ring trap have been found. If only levels of the radial motion close to the bottom of the potential well of the trap are populated considerably, the oscillatory model of the single-particle spectrum is applicable. In this case, even the strong exciton–exciton interaction can be taken into account.     

Magnetoplasma oscillations of a two-dimensional electron system with spin-orbit interaction in a lateral superlattice

Low-frequency magnetoplasmon modes in a one-dimensional lateral superlattice with Rashba spin-orbit splitting are considered. Such modes correspond to oscillations related to virtual transitions within a Landau level that become possible due to the broadening of each Landau level into a band produced by the superlattice potential. The specificity of the one-dimensional intersubband plasmons emerging in such a system has been revealed.     

Spin-dependent electron localization in crystals

The possibilities of spatially localizing spin-polarized electrons in two-dimensional and three-dimensional systems due to spin-orbit interaction are studied theoretically. Using simple one-dimensional potentials as examples, it is demonstrated that electrons with a definite helicity can be localized so that carrier separation by spin is accomplished. The magnetic field effect is studied, and it is shown that the position of bound levels depends substantially on this effect.     

Energy transfer in hybrid systems quantum dot–plasmonic nanostructures

Radiationless relaxation in hybrid systems quantum dot (QD)–plasmonic nanostructure is considered. For the system QD–2D plasma the relaxation rate extremely steeply depends on the radius of quantum dot while in the pair QD–cylindrical wire contacting each other this dependence is logarithmic weak.