Model for degradation of band-gap photoluminescence in GaAs

A recombination-enhanced defect reaction model is described. It is based on nonradiative recombination of photoexcited carriers at particular crystal defect sites near a semiconductor surface. The model is general and correctly predicts, with only one adjustable parameter, the photoluminescence degradation rate in GaAs, its power dependence, and its independence on lattice temperature.