Optoelectronic properties of Cd1−<i>x</i>Zn<i>x</i>Te films grown by molecular beam epitaxy on GaAs substrates

Abstract

Photoluminescence (PL) experiments were carried out at 300 and 12 K to investigate the electro-optical properties of Cd1−xZnxTe grown by molecular beam epitaxy on GaAs substrates. The compositional dependence of the band-gap energy was determined. It has a quadratic dependence on x. The near band edge PL spectra at 12 K show free and bound exciton lines for x=0 and 1 and only broadened bound exciton peaks for other compositions. The bound exciton broadenings are quantitatively explained based on the compositional fluctuations of the cations. The PL line shapes give indications of the high quality of the layers.