Strong carrier localization in Sb-terminated InGaAs/AlAsSb quantum wells grown by molecular beam epitaxy

We report here on a study of the photoluminescence (PL) and photoreflectance (PR) spectra from InGaAs/AlAsSb multiple quantum wells with antimony interface terminations that were grown by molecular beam epitaxy. The PL spectrum exhibits a broad peak between 4 and View the MathML source, composed of interface-related transitions and transitions between confined energy levels in the well (EC). Features of the quantum well related interband transitions (EnHm) are clearly observed in the PR spectra between 55 and View the MathML source. Below View the MathML source, EC shifts significantly toward lower energy from E1H1, indicating strong carrier localization.