The Mn concentration dependence of photoluminescence spectra in CdMnTe/CdMgTe quantum Hall system at high magnetic fields up to 25 T

Abstract

We performed polarized photoluminescence (PL) experiments in the quantum Hall system of II–VI semiconductors, Cd 1− x Mn x Te/CdMgTe single quantum well at steady magnetic fields up to 25 T. The evolution of the spectra with changing Mn concentration x was investigated. In CdTe/CdMgTe quantum well ( x=0), the oscillatory behaviors of the PL due to the many-body effect were observed at the integer filling factor clearly. In the lower Mn sample, the effective g-factor of electron was tuned to nearly zero and the PL was polarized in σ + polarization because of the gigantic Zeeman splitting in the valence band. The observation of the Auger and spin-flip recombination processes around ν∼3 supports this situation. In the higher Mn sample, the PL is also highly polarized in σ + polarization due to the large Zeeman splitting of both the conduction band and the valence band. The sudden shift of the PL energy was observed at the filling factor ν=1 only for the higher Mn sample.