Temperature dependence of the effective mobility edge and recombination dynamics of free and localized excitons in InGaP/GaAs quantum wells

The temperature dependence of the effective mobility edge in semiconductor quantum wells containing disorder is reported for the first time. It is deduced by reproducing the experimental continuous wave and time resolved luminescence spectra by means of a two-class exciton kinetic model, which considers the co-existence of free and localized excitons and introduces a mobility edge defined by a Fermi function. The mobility edge varies faster than the PL peak energy when the temperature increases, passing from the high energy side of the PL band at low temperatures (recombination of localized excitons dominates) to the low energy side above View the MathML source (recombination of quasi-free excitons dominates).