Temperature quenching of photoluminescence of ordered GaInP2 alloy under different excitation densities

The photoluminescence (PL) emission from an epi-structure containing an atomically ordered GaInP2 layer and a GaAs layer was studied under excitation power densities of 0.03 - 3 W/cm(2) at temperatures of 10 to 300 K. The quenching of the integrated PL intensity from both: the GaInP2 and the GaAs layers is stronger under low excitation, than under high excitation density. The temperature dependence, however, have different shapes being the PL decay observed for the GaInP2 layer stronger than that for the GaAs layer. Comparing the temperature dependence of the PL intensity from the ordered GaInP2 and the GaAs layers under different excitation densities and analyzing them together, we conclude that the inhomogeneity of the ordered layer is responsible for the different temperature behavior of the GaInP2 alloy PL emission. To explain the experimentally observed PL intensity temperature dependence an additional nonradiative recombination mechanism due to a thermally activated escape of the carriers from its confinement within regions of lower bandgap has to be taken into account.