Raman scattering by the coupled plasmon LO-phonon modes near the E0 0 gap of n-type GaAs: Resonance and interference effects

The semiclassical model of Klein, extended to the case of an absorbing medium, is used to discuss Raman scattering by coupled plasmon LO-phonon modes in n-type GaAs near the E0 0 gap. A reasonably quantitative agreement between the calculated and measured squared Raman polarizabilities is found below resonance, whereas additional assumptions are necessary to achieve comparable results above it. Exactly at resonance, the model predicts a behavior somewhat different from the observed one.