Professor Robert Taylor

Abstract:

We report the results of a systematic investigation of the stimulated emission in ZnSSe/ZnSe superlattices, by time resolved luminescence and high excitation intensity magnetoluminescence. The stimulated emission is found to have excitation origin from localized states around the threshold, and free-carrier origin at carrier densities well above the phase space filling threshold of the exciton. © 1994 Academic Press Limited.

Abstract:

We have measured the energy relaxation of hot carriers in doped and undoped GaAs/AlxGa1-xAs quantum wells by detecting time-resolved hot luminescence using a two-pulse intensity correlation technique. The results are compared with time-dependent intensity correlation functions calculated using a model of energy relaxation by optical phonon interactions which includes non-equilibrium phonon effects. The excellent agreement between calculated and experimental correlation functions shows the great potential of this method in measuring ultrafast relaxation processes. © 1994.

Abstract:

We report optical studies of MBE-grown ZnTe/GaSb. Main impurities and free exciton resonances are determined, and polariton-phonon scattering is observed. We also report time-resolved photoluminescence studies, yielding an estimate of the LO phonon lifetime in ZnTe. © 1994.