Exciton spin dynamics and polarized luminescence in quantum wells

Abstract

The time evolution of the polarized luminescence is used to provide a better understanding of the relaxation processes of excitons in quantum wells. We established and solved a coupled set of rate equations for the exciton spin populations in which the spin relaxation mechanisms include the exchange interaction and individual spin-flip of the electrons and holes. A time-dependent energy distribution for the excitons is used to account for the thermalization effect. The dependence of the exchange-driven channel on a longitudinal electric field is shown to be useful in determining its relative importance among various competing spin relaxation channels. © 1994.