High Pressure Photoluminescence Study of the GaAs/Partially Ordered GaInP Interface

Using time-resolved (TRPL) and continuous-wave photoluminescence (CWPL) we have studied GaAs/partially ordered Ga0.5In0.5P single quantum well samples at pressures up to ≈5 GPa. In such samples emission from the quantum well is only seen if intermediate GaP layers are grown between the GaAs and GaInP and is otherwise masked by anomalous bands at around 1.46 eV. Examination of the TRPL spectra shows large differences in the pressure dependence of this emission because of the inequivalence of the GaAs/GaInP interfaces. For the sample with no thin GaP layer between the upper interface this emission has a very long PL-decay time and a stronger blueshift with excitation intensity at higher pressures. The pressure-dependent PL behavior at lower excitation intensity is close to that of the GaInP barrier. The 1.46 eV emission can be attributed to the spatially indirect transitions at the interface with no GaP layer.