Photoluminescence of ZnSexTe1-x/ZnTe multiple-quantum-well structures grown by molecular-beam epitaxy

Abstract

This work investigates photoluminescence (PL) spectra from ZnSexTe1-x/ZnTe multiple-quantum-well structures grown on GaAs(001) substrates by molecular-beam epitaxy. The PL data reveal that the band alignment of the ZnSexTe1-x/ZnTe system is type II. The thermal activation energy for quenching the PL intensity was determined from the temperature-dependent PL spectra. The activation energy was found to increase initially and then decrease as the thickness of the ZnSexTe1-x layers decreases from 7 to 3 nm. The temperature-dependent broadening of the PL linewidth was also investigated. The LO-phonon scattering was found to be the dominant broadening mechanism. (C) 2004 American Institute of Physics.