Giant blue shift of photoluminescence in strongly excited type-II ZnSe/BeTe superlattices

Abstract

A giant blue shift (≈0.5 eV) and a large decrease in the emission time of a spectral band corresponding to radiative recombination of spatially separated electrons and holes are observed in ZnSe/BeTe superlattices at high laser excitation levels. On the basis of numerical calculations, the observed defects are attributed to band bending arising in type-II structures at high carrier density.