Low-temperature kinetics of localized excitons in nanostructures

We have developed a theory of low-temperature energy relaxation of localized excitons in semiconductor quantum wells and quantum wires. The steady-state population of the exciton-band tail and hence the photoluminescence spectrum are determined as a result of competition between exciton radiative recombination and multiple hopping from higher to lower energy levels. An effect of correlation in the successive hops has been taken into account and has been estimated numerically for systems of different dimensionality. Time-resolved photoluminescence spectra for pulsed excitation have also been calculated and compared with the steady-state photoluminescence spectrum. (C) 1996 Optical Society of America