We study, within the Hartree approximation, the effects of the electronelectron interaction on the energy spectrum of a two-dimensional electron gas in a perpendicular homogeneous magnetic field and a lateral superlattice potential with square symmetry. Due to the strong screening effects, the bandwidth of the Landau bands oscillates strongly with their filling. For short enough periods and str...

We examine the phenomenon of electromagnetic transparency in semiconductor superlattices having various miniband dispersion laws in the presence of multi-frequency periodic and nonperiodic electric fields. Effects of induced transparency and spontaneous generation of static fields are discussed. We pay special attention to self-induced electromagnetic transparency and its correlation to dynamic...

We describe a limiting case when nonlinear dynamics of an ac-driven semiconductor superlattice in the miniband transport regime is governed by a periodically forced and damped pendulum. We find analytically the conditions for a transition to chaos, as well as the conditions for absence of chaosat any amplitude of ac drive. We also discuss fractional dc voltage states in a superlattice originati...

We consider the motion of ballistic electrons within a superlattice miniband under the influence of an alternating electric field. We show that the interaction of electrons with the self-consistent electromagnetic field generated by the electron current may lead to the transition from regular to chaotic dynamics. We estimate the conditions for the experimental observation of this deterministic ...

We report the operation of a Bloch oscillator. The active medium was a staticvoltage driven, doped GaAs/AlAs superlattice which was electromagnetically coupled to a resonator. The oscillator produced tuneable microwave radiation (frequency ~ 60 GHz; power ~ 0.5 mW; efficiency ~ 4 %). The gain (~ 10 cm) was due to the nonlinearity mediated by miniband electrons. We also present a theory of the o...

The thermal power (PF = S2Ge) depends on the Seebeck coefficient (S) and electron conductance (Ge). enhancement of Ge will unavoidably suppress S because they are closely related. As a consequence, optimization PF is extremely difficult. Here, we theoretically investigated thermoelectric properties two-dimensional quantum dot (QD) arrays with carriers injected from electrodes. Lorenz number 2D ...

The influence of interface electron scattering on electron mobility in semiconducting quantum wells is analyzed theoretically in the Born approximation. The interface roughness is assumed to be random self-affine fractal characterized by roughness exponent H, correlation length x, and rms amplitude D. In particular, the ratio of electron mobilities for the Fermi level slightly above and below t...

The generalized Kubo-Greenwood formula for conductivity is used for an explicit calculation of the perpendicular conductivity of GaAs-AlGaAs (crystalline III-V) heterostructures. Two cases are discussed (a) evaluation of DC conductivity at low temperatures and (b) AC conductivity at any temperature T. The method involves the causal Green’s function and relates the conductivity with superlattice...