Exciton dynamics and recombination in ZnSe/ZnSe0.82S0.18 superlattices
We report time-resolved optical transmission and photoluminescence measurements of exciton dynamics and recombination in a ZnSe/ZnSe0.82S0.18 superlattice which displays low-threshold lasing. The carrier densities in our experiments are below threshold for stimulated emission. We find clear evidence for strong exciton-LO phonon scattering which gives rise to emission at the same wavelength where stimulated emission is reported to occur.