Homogeneous-linewidth dependence of resonant Raman scattering in GaAs quantum wells

We demonstrate the LO-phonon Raman intensity in GaAs/AlAs multiple quantum wells to be inversely proportional to the exciton homogeneous linewidth for photon energies resonant with the band-edge exciton. The strongest Raman scattering is seen at the low-energy side of the exciton peak, where the homogeneous linewidth is narrowest. The energy dependence of the linewidth deduced from the resonance Raman profile agrees well with that measured directly by degenerate-four-wave mixing.