Kinetics of exciton photoluminescence in type-II semiconductor superlattices

The exciton decay rate at a rough interface in type-II semiconductor superlattices is investigated. It is shown that the possibility of recombination of the indirect excitons at a plane interface essentially affects the kinetics of the exciton photoluminescence at a rough interface. This is the result of the quantum interference of electrons scattered from the plane interface and at the roughnesses. Expressions that relate the parameters of the luminescence kinetics with the statistical characteristics of the rough interface are obtained. The mean height and length of the roughnesses in GaAs/AlAs superlattices are estimated from the experimental data.