STRAIN-DEPENDENT OPTICAL PHONON FREQUENCIES OF CUBIC ZNS

Bulk ZnS crystals have been examined by Raman spectroscopy at room tem perature under uniaxial stress. Both transverse optical and longitudin al optical frequencies exhibit shifts which are Linear in the stress. From the observed slopes we obtain the complete set of phonon deformat ion potentials which, in turn, are used to predict the LO phonon frequ ency shifts in strained ZnTe/ZnS and ZnSe/ZnS superlattices as a funct ion of the layer thickness. The results are in agreement with previous ly reported values obtained from Raman measurements in such superlatti ces. (C) 1998 American Institute of Physics.