Generalization of the hydrodynamical model to analyze Raman scattering by free carriers: application to n-InP

The results of free-carrier density evaluation by means of Raman scattering in doped semiconductors strongly depend on the electric susceptibility mod el used to calculate Raman line shapes. Although the Lindhard-Mermin model has proved to yield accurate results over a wide range of free-charge densi ties, it involves a fair amount of numerical calculations, and simpler thou gh less accurate models such as the Drude and the hydrodynamical models are widely used. We propose an extension of the hydrodynamical model in which nonparabolicity and temperature effects are taken into account. The resulti ng extended model retains the simplicity of the hydrodynamical model and ye t it improves significantly the agreement with the results of the Lindhard- Mermin model. (C) 2000 Elsevier Science B.V. All rights reserved.