Quantum-Dimensional Near-Surface Recombination of Photocarriers in CdTe Microcrystals

A study is performed of low-temperature ( T = 2 K) photoluminescence spectra of a p -CdTe/ n -CdS film heterostructure containing CdTe microcrystals. a dominant superhot radiation band is found in the spectral region above the intrinsic absorption edge of bulk CdTe. The band arises because of optical transitions of electrons from near-surface levels of the spatial quantization of a microcrystal to the valence band states.