Reflectivity and transmissivity of a slab caused by the stimulated Raman effect

It is shown that as a result of anharmonic coupling of the polariton waves, Stokes and anti-Stokes waves by a pump wave, an irradiated second wave (two-beam method) generates new waves from a slab. The frequency of the irradiated wave can be chosen from the Stokes and anti-Stokes visible region or from the polariton in the infrared region. First numerical results are given for GaP for reflectivity in the polariton and in the Stokes visible region. The spectra show strong amplification of the irradiated wave.