Light Scattering by Plasmons and Landau Levels of Electron Gas in InAs

We report the observation of inelastic scattering of 10.6 μ radiation by collective and single-particle cyclotron excitations of mobile carriers in InAs. The observed cross sections of ∼${10}^{-25\mathrm{}}$ ${\mathrm{cm}}^2$ ${\mathrm{sr}}^{-1\mathrm{}}$ for both the plasmon and the Landau-Raman $\Delta l=1\mathrm{}$ and $\Delta l=2\mathrm{}$ scattering processes are in agreement with calculations. Raman scattering of light by optic phonons is found to be at least a factor of 100 weaker than the plasmon scattered light. Effects of magnetic field on plasmon scattering are also described.