Resonant Raman Scattering fromAlxGa1−xAs

We report the results of a detailed study of resonant Raman scattering from the mixed crystal ${\mathrm{Al}}_x{\mathrm{Ga}}_{1-x}\mathrm{As}$ at 2 °K using a continuously tunable dye laser. The dye laser enables us to obtain the exact resonance line shape. Comparison of the resonance behavior of the GaAs-like and the AlAs-like LO phonons allows us to determine the energy of the band gap accurately. In addition to the resonance behavior, we have also studied the 1-LO linewidths and line shapes, the behavior of the TO phonon and local modes, and also certain broad luminescence features present in the spectra.