Strain-induced band-mixing effects in CdTe/ZnTe (001) superlattices

The electronic bandstructures of the strained CdTe/ZnTe (001) superlattices (SLs) are investigated using the sp3s* tight-binding method, which includes the spin–orbit coupling and biaxial strain effects. The calculated bandstructures are studied versus the biaxial strain, SL layer thicknesses and valence-band offset (VBO). This SL has been chosen as a model for the vanishing-VBO heterostructures, such as the case of common-anion II–VI SLs. The results show that the electron is always confined within the CdTe slabs, whereas the hole is sensitive to the biaxial strain. Our theoretical results are further compared to the photoluminescence experiments and are shown consistent with the strain morphology along the SL growth direction, as well as the optical and structural qualities of the experimental samples.