Dephasing oftheLH-HHexciton Ramancoherence inGaAs quantumwells: distinguishing between phononandcarrier scattering

Three-beam four-wave mixing shows anti-correlated scattering ofHHandLHexcitons inGaAs/AlGaAs quantum wells, suggesting that exciton-phonon scattering dominates theexciton dephasing. Thecorrelation increases athigher excitation densities. ©2005Optical Society ofAmerica OCIScodes: (320.7130) Ultrafast processes incondensed matter; (190.4380) Nonlinear optics, four-wave mixing; (190.5970) Semiconductor nonlinear optics including MQW;(190.7110) Ultrafast nonlinear optics