Mechanism of the effect of the electric field of a surface acoustic wave on the low-temperature photoluminescence kinetics in type-II GaAs/AlAs superlattices

Kinetics of the low-temperature photoluminescence (PL) of type-II GaAs/AlAs superlattices under the effect of the electric field of a surface acoustic wave is studied experimentally. It is found that application of electric-field pulses results in speeding up the PL kinetics of free and localized excitons and phonon replicas irrespective of the pulse duration. Analysis of the experimental data demonstrates that acceleration of the PL kinetics is related to the transport of excitons towards nonradiative recombination centers; this transport is promoted by the interaction of excitons with hot free charge carriers ejected from localized states.