Electrical and optical time-of-flight experiments in GaAs/AlAs superlattices

Abstract

The dynamics of electron transport by sequential resonant and nonresonant tunneling along the growth direction of tight-binding GaAs/AlAs superlattices is studied by electrical time-of-flight experiments and by time-resolved photoluminescence. In the limit where the decay time of the photoluminescence is determined by transport (and not by recombination), we observe structures in the field dependences of both the optical and electrical response times which are related to resonances between different electronic subbands of adjacent wells. Here the time-resolved photoluminescence and the electrical time-of-flight experiment provide independent tools to investigate the dynamics of the conduction processes.