Photoluminescence of ultrathin ZnSe-ZnTe superlattices

Abstract ZnSe-ZnTe superlattices were grown on GaAs (100) surfaces by molecular beam epitaxy without buffer layer. The thicknesses of ZnSe and ZnTe layers were varied from 5/4 to 9/4 monolayer (ML) and from 1/9 to 1 ML, respectively. The photoluminescence (PL) spectra due to isoelectronic traps of Te atoms and clusters are independent to the thickness of ZnSe layers. We can tune the photon energy of PL emission from about 2.65 to 2.35 eV under the thickness of ZnSe layers of 2 monolayers constant. The green emission was achieved at room temperature by the superstructure with blue band layers sandwiched by ZnTe of 1 ML.