Optical study of residual strains in CdTe and ZnTe layers grown by molecular beam epitaxy on GaAs

Abstract
Residual strains in (001) and (111) thick layers of CdTe and ZnTe grown by molecular beam epitaxy on nominal or slightly tilted (001) GaAs have been investigated by reflectance, photoluminescence, and optical pumping experiments at low temperature. Strains are found to be independent of both layer orientations and thicknesses in the range 2–6 μm. They are compressive ≊−0.5×103 in CdTe and tensile ≊103 in ZnTe. Estimates of thermal expansion effects show that they are the dominant cause of residual strains in these heterostructures.