Band offsets and lattice-mismatch effects in strained-layer CdTe/ZnTe superlattices

Abstract

We present a detailed investigation of the combined effects of band offsets and lattice mismatch on the subband structure of strained-layer CdTe/ZnTe superlattices. It is shown that, depending on the layer thicknesses, the superlattice may either have a type-I configuration, where electron and hole are mostly localized within CdTe layers, or a type-II configuration. Moreover, the hole ground state may either be the heavy-hole subband or the light-hole one. The results are compared with photoluminescence data and the value \ensuremath{\Delta}${E}_{v}$=60\ifmmode\pm\else\textpm\fi{}20 meV is obtained for the zero-strain valence-band offset.