CALCULATIONS OF THE NONLINEAR ACOUSTOELECTRIC CURRENT IN A DOPING SUPERLATTICE GaAs:Si/GaAs:Be IN THE PRESENCE OF AN ELECTROMAGNETIC WAVE

Tóm tắt

The nonlinear acoustoelectric (NAE) current in a doping superlattice (DSL) is investigated for an acoustic wave in the region ql>>1 (where q is the acoustic wave number) in the presence of an electromagnetic wave. The dependence of the NAE current jNAE on the frequency of external acoustic wave q, the temperature T, the amplitude E0 and frequency of the electromagnetic wave  are obtained by using the quantum kinetic equation for electron-external acoustic wave interaction and electron-acoustic phonon (internal acoustic wave) scattering. Numerical calculation is done, and the result is discussed for a typical GaAs:Si/GaAs:Be DSL. The computational results show that the dependence of the NAE current jNAE on the external acoustic wave frequency q, the frequency of electromagnetic wave  and the characteristic parameters of DSL is non-monotonic andthe cause of appearance peaks attributes the transition between mini-bands. The quantum theory of the NAE current in a GaAs:Si/GaAs:Be DSL is newly developed.