Differential measurements of Raman coherence and of dynamically interacting excitons in quantum wells

Abstract

Quantum beats involving the light and heavy hole excitons in GaAs quantum wells are studied using both conventional and novel temporally-gated differential detection techniques. The contributions of dynamic exciton-exciton correlations are separated from the nonradiative contributions of Raman coherence by monitoring the signal in the unconventional probe direction and by taking advantage of the polarization selection rules for the excitonic transitions.