Quenching of the spontaneous current oscillations in GaAs/AlAs superlattices under domain formation

Abstract

Self-sustained current oscillations in a dc biased GaAs/AlAs superlattice exhibiting domain formation can be quenched by applying an external ac driving voltage with a large amplitude. The frequency of the driving voltage has to be much larger than the oscillation frequency and the well-to-well hopping frequency of the domain boundary. Under this condition, the oscillations of the domain boundary cannot follow anymore the ac driving signal. Consequently, for a fixed dc bias voltage the accumulated charge forming the domain boundary is confined within a single quantum well resulting in stationary domains.