Zn1−<i>y</i>Cd<i>y</i>Se1−<i>x</i>Te<i>x</i> quaternary wide band-gap alloys: Molecular beam epitaxial growth and optical properties

Abstract

We report the growth of Zn1−yCdySe1−xTex alloys by molecular beam epitaxy on GaAs substrates. The optical properties and the band structure of this new material have been investigated. The compositional dependence of the quaternary band gap was studied using photoconductivity measurements and is well described by a third degree function of x and y. Photoluminescence spectra at low temperature show a single broad band, which narrows with increasing Te composition. We discuss the applicability of this new material for ZnSe/ZnCdSeTe heterostructures and predict a region of optimal band offsets for useful confinement of both electrons and holes.