Strain-assisted bandgap modulation in Zn based II-VI semiconductors

Abstract

The electronic structure of bulk ZnX (X = O, S, Se, and Te) under uniaxial strain along the [0001] direction or equibiaxial strain along the (0001) plane is investigated using hybrid density functional theory calculations and many-body perturbation theory. It is shown that compressive uniaxial (or tensile equibiaxial) strains lead to a structural phase transition in all the ZnX systems. This is accompanied by large reductions in the bandgap of ZnSe and ZnTe, spanning the entire visible spectrum.