Determination of the dispersion of the index of refraction and the elastic moduli for molecular-beam-epitaxy-grown Zn_(1-x)Be_(x)Se alloys

摘要

The prism coupler technique, together with reflectivity channeled spectra, were used to determine the dispersion of the indices of refraction for a series of ternary alloys of Zn_(1-x)Be_(x)Se grown by molecular-beam epitaxy on GaAs substrates. The measurements covered the wavelength range of 400-1300 nm, and the entire Be concentration range, from x=0 to 1.00. The availability of accurate values of the index-of-refraction then enabled us to determine the elastic moduli c_(11) for the Zn_(1-x)Be_(x)Se and its dependence on the Be concentration x from frequency shifts in Brillouin scattering spectra observed on the epilayers of these ternary alloys. The c_(11) results clearly indicate that the bonding in Zn_(1-x)Be_(x)Se becomes more robust as the Be concentration increases.