Picosecond luminescence study of hot-carrier relaxation in 1.3-μm In0.72Ga0.28 As0.6P0.4

Abstract

We report measurements of luminescence spectra of ${\mathrm{In}}_{0.72}$ ${\mathrm{Ga}}_{0.28}$ ${\mathrm{As}}_{0.6}$ ${\mathrm{P}}_{0.4}$ with < 10 psec time resolution and a wide dynamic range. The spectra are dominated by band-to-band recombination processes. Analyses of the high-energy tails of the spectra allow a determination of carrier temperatures. From the measured variation of carrier temperatures with time, we show that the carrier energy-loss rates to the lattice depend on excitation intensity and are lower than expected on the basis of a model that takes into account the four optical-phonon branches in this semiconductor.