Localization and interdot carrier transfer in CdSe and CdZnMnSe quantum dots determined by cw and time-resolved photoluminescence

Abstract

The authors compared time-integrated and time-resolved photoluminescence (PL) emitted by CdSe quantum dots (QDs) and by CdZnMnSe QDs. An unusual nonmonotonic temperature dependence of the PL shift for CdSe QDs is observed, which they ascribe to delocalization of carriers with increasing temperature. In contrast, PL emitted by CdZnMnSe QDs follows a typical monotonic redshift with temperature and exhibits a smaller temporal redshift with pulsed laser excitation than that observed for CdSe QDs. The authors suggest that the temperature PL dependence observed for CdZnMnSe QDs and the smaller localization process observed in that system arise from the shorter PL lifetime in that system.