Study of Zn1-xMgxSe and Zn1-xBexSe semiconducting crystals by Raman scattering

Wide gap II-VI mixed crystals containing Mg and Be are recently studied extensively for their application in constructing blue-green laser diodes. This work deals with experimental study of optical modes in Zn1-xMgxSe and Zn1-xBexSe semiconductors using Raman scattering method. Measurements have been performed at room and Liquid nitrogen temperatures for Zn(1-x)Mt(x)Se crystals with Mg content in the range 0 < x < 0.34 and for Zn1-xBxSe with Be content in the range 0 < x < 0.26. From polarized Raman spectra longitudinal (LO) and transverse (TO) optical modes corresponding to ZnSe- and MgSe-like modes in Zn1-xMgxSe and to ZnSe- and BeSe-like modes in Zn1-xBexSe were determined. These lattice vibrations can be described by the modified random element isodisplacement (MREI) model.