SUPER BAND-GAP TIME-RESOLVED LUMINESCENCE STUDY OF DEGENERATE ELECTRON-HOLE PLASMA IN THIN GAAS EPILAYERS

Super band-gap time-resolved photoluminescence is employed to measure the transport properties of degenerate electron-hole gas in thin GaAs epilayers. It is found that the luminescence decay at wavelengths shor ter then the energy gap wavelength is much faster then expected from a simple diffusion-reabsorption model. The results are explained by usi ng a transport model based on Fermi-Dirac carrier statistics and nonpa rabolic band structure. We have found that only by introducing the abo ve two phenomena the photoluminescence spectra at all energies can be fitted. The importance of the results in studies of hot carrier energy loss rates is discussed. (C) 1996 American Institute of Physics.