Influence of misfit dislocations on thermal quenching of luminescence in InxGa1−xAs/GaAs multiple quantum wells

The temperature dependence of the cathodoluminescence (CL) originating from In0.21Ga0.79As/GaAs multiple quantum wells has been studied between 86 and 250 K. The CL intensity exhibits an Arrenhius‐type dependence on temperature (T), characterized by two different activation energies. The influence of misfit dislocations and point defects associated with strain relaxation on the thermal quenching of luminescence has been investigated, and the spatial variation in the activation energies has been examined. The CL intensity dependence on temperature for T≲150 K is controlled by thermally activated nonradiative recombination. For T≳150 K the decrease in CL intensity is largely influenced by thermal re‐emission of carriers out of the quantum wells.