Photoluminescence characterization of GaAs/GaAs0.64P0.19Sb0.17/GaAs heterostructure

Interfacial characteristics of GaAs/GaAs0.64P0.19Sb0.17GaAs heterostructures and emission properties of a quaternary GaAs0.64P0.19Sb0.17 layer were studied by excitation-power- and temperature-dependent photoluminescence (PL) measurements. The GaAs-to-GaAsPSb upper interface related emission feature and signals from GaAsPSb and GaAs were observed and characterized. The upper interface related emission peak was attributed to the radiative recombination of spatially separated electron–hole pairs and suggesting the type-II alignment at the GaAs/GaAsPSb interface. The localized excitonic emission feature of GaAsPSb revealed a blueshift due to the saturation effect of localized states and showed a fast thermal-quench with the increase of temperature. The temperature variation of the band edge emission signal of GaAsPSb was found to follow that of GaAs closely.