EFFECTS OF N-TYPE MODULATION DOPING OF QUANTUM-WELLS ON THE DYNAMICS OF PHOTOLUMINESCENCE

The rise time of band-edge photoluminescence (PL) in n-type modulation -doped quantum-well structures has been studied. The PL turns on less than 1 ps after carriers are photoinjected into the conduction band, o r six times more rapidly in the n-doped structures than in comparable undoped structures. This is attributed to the rapid intraband relaxati on of holes and the presence of a large ambient electron population du e to the doping. We discuss the implications of this result for the di rect modulation bandwidth of n-type modulation-doped quantum-well lase rs.