Abstract

Thermalization of photoexcited carriers in polar semiconductors occurs on a sub-picosecond time scale and has been investigated in various experiments with femtosecond laser pulses. In most cases, transient Absorption changes have been studied in spectrally and temporally resolved pump-probe experiments. Electrons and holes in different regions of k-space contribute to bleaching at a specific probe wavelength and, consequently, unambiguous information on carrier equilibration is difficult to extract from the data. Femtosecond luminescence spectroscopy provides new information about the temporal evolution of the electron and hole distributions because luminescence at a specific wavelength requires the presence of both electrons and holes at the same k-vector.

© 1992 Optical Society of America