Time-resolved photoluminescence studies of InxGa1-xAs1-yNy

Time-resolved photoluminescence spectroscopy has been used to investigate carrier decay dynamics in a InxGa1-xAs1-yNy (x similar to 0.03, y similar to 0.01) epilayer grown on GaAs by metal organic chemical vapor deposition. Time-resolved photoluminescence (PL) measurements, performed for various excitation intensities and sample temperatures, indicate that the broad PL emission at low temperature is dominated by localized exciton recombination. Lifetimes in the range of 0.07-0.34 ns are measured; these photoluminescence lifetimes are significantly shorter than corresponding values obtained for GaAs. In particular, we observe an emission energy dependence of the decay lifetime at 10 K, whereby the lifetime decreases with increasing emission energy across the PL spectrum. This behavior is characteristic of a distribution of localized states, which arises from alloy fluctuations. (C) 2000 American Institute of Physics. [S0003-6951(00)03702-5].