Gunn oscillations up to 20 GHz optically induced in GaAs/AlAs superlattice

Abstract

Direct observation of Gunn oscillations up to 20 GHz, induced by picosecond light pulses in an undoped GaAs/AlAs superlattice, is reported. They are obtained in the superlattice growth direction and from 7 K up to room temperature. The frequency is strongly dependent on the applied bias voltage and on the photoexcited carrier density. The oscillation frequency and the mode of operation are modeled by a classical numerical simulation.