Collision-narrowing of Raman spectrum for spin-density fluctuations of electrons in n-GaAs

The inelastic light-scattering spectrum for single-particle excitations in n-GaAs has been found to be considerably $\text{narrower}$ than the Gaussian form usually predicted for a Maxwell-Boltzmann energy distribution. In this paper, we compare the contribution to the narrowing for two factors: collisions and the momentum-dependence of resonant enhancement terms. The analysis is restricted to the spin-density fluctuation mechanism, which has been found to be best suited for probing the electron distribution.