Determination of the dispersion of the index of refraction and the elastic moduli for molecular-beam-epitaxy-grown $Zn1−xBexSe$ alloys

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 $Zn1−xBexSe$ 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 $c11$ for the $Zn1−xBexSe$ and its dependence on the Be concentration $x$ from frequency shifts in Brillouin scattering spectra observed on the epilayers of these ternary alloys. The $c11$ results clearly indicate that the bonding in $Zn1−xBexSe$ becomes more robust as the Be concentration increases.