HIGH-FIELD MINIBAND TRANSPORT IN SEMICONDUCTOR SUPERLATTICES IN PARALLEL ELECTRIC AND MAGNETIC-FIELDS

We present a rigorous quantum-mechanical description of the miniband t ransport in semiconductor superlattices under the mutual influence of high electric and magnetic fields aligned parallel to the growth direc tion. Strong current oscillations appear due to Landau and Wannier-Sta rk quantization of the electronic states and due to the scattering on polar-optical phonons. The combined influence of an electric and magne tic field on magnetophonon and electrophonon resonances is treated by a lateral electron distribution function, which is the solution of a q uantum-kinetic equation. The lateral electron heating due to the field dependent coupling between longitudinal and transverse degrees of fre edom via the distribution function is essential to understand miniband transport properties of superlattices. Intracollisional field effects are taken into account. Strong magnetic fields lead to a pronounced e nhancement of Wannier-Stark current oscillations. The experimentally d etected crossover in the temperature dependence of the current is repr oduced. The influence of an electric field on magnetophonon resonances is investigated. [S0163-1829(97)02847-6].