Temperature-dependent optical properties of InAs∕GaAs quantum dots: Independent carrier versus exciton relaxation

We have performed temperature-dependent studies of the photoluminescence properties of a range of InAs∕GaAs quantum dot structures. Changes in the temperature dependence of the peak energy and spectral width are governed by thermally stimulated transfer processes and hence depend on the depth of the confining potentials. We have compared our experimental results with detailed calculations based upon correlated electron-hole (exciton) or independent electron-hole relaxation. We conclude that at elevated temperatures the carrier dynamics are governed by independent carrier relaxation.