Resonant Rayleigh Scattering from an Inhomogeneously Broadened Transition: A New Probe of the Homogeneous Linewidth

Abstract
Strong elastic scattering of laser light, up to 200 times background, is found at the exciton resonance of GaAs/AlGaAs multi-quantum-well structures. It is shown to be a consequence of spatial fluctuations of the refractive index due to inhomogeneous broadening of the resonance. The frequency and temperature dependence of the homogeneous linewidth can be obtained from the data.