Correlation between the exciton mobility and the excitonic linewidth in shallow InxGa1minus;xAs/GaAs quantum wells

摘要

Using timehyphen;resolved photoluminescence (PL) spectroscopy with high spatial (0.1 mgr;m) and temporal (50 ps) resolution, we have investigated exciton scattering in a set of strained InxGa1minus;xAs/GaAs quantum wells as a function of well widthLzand In contentx. Summarizing the results, a strong correlation between the exciton mobility and the emission linewidth (LW) is found: High mobilities correspond to small luminescence LWs, indicating reduced exciton scattering. From the dependence of the excitonic mobility on temperature and In contentx, we conclude, that interface roughness scattering and alloy scattering, respectively, are the dominant processes controlling the mobility as well as the PL LW at low temperatures.