Magnetic field dependence of exciton linewidth in quantum wells made of semimagnetic semiconductors: comparison of theory and experiment

摘要

This paper presents the result of theoretical and experimental studies of the magnetic field dependence of the exciton linewidth in Cd1-yMgyTe/Cd1-xMnxTe/Cd1-yMgyTe quantum wells. The reflection spectra from the structures with various values of x were measured at T = 2 K in magnetic fields up to 3.5 T applied parallel to the structure's growth axis. In the theoretical studies, the fluctuations of both concentration and spin projection of magnetic ions have been considered as the main reasons for the exciton line broadening. It is shown that the experimentally observed broadening of the sigma(-) exciton line and the narrowing of the sigma(+) exciton line with increasing magnetic field are in good agreement with theoretical calculations.