Thermal escape and carrier dynamics in multilayer CdTe/ZnTe quantum dots

Abstract We present an optical spectroscopy study of multilayer CdTe/ZnTe quantum dots by photoluminescence (PL) and time-resolved PL. We demonstrate that the PL blueshift and enhanced PL intensity were due to an increase in the material intermixing and the density of the emitting states. An integrated PL as a function of temperature revealed that the separated energy of two different states was 4.5–6.2 meV and was nearly independent of the stack period. The main thermal escape was assisted by multi-longitudinal optical phonons at high temperature with activation energies in the range 48–54 meV.