Light Scattering by Coherently Driven Lattice Vibrations

Observations of Raman scattering from intense coherently driven lattice vibrations in calcite are reported. The lattice vibrations ($\overline{\nu }\left(A_1\right)=1086\mathrm{}$ ${\mathrm{cm}}^{-1\mathrm{}}$) are produced by the stimulated Raman effect, and the scattering is observed with low-intensity monochromatic probe sources in the red and ultraviolet. The Raman-scattered light is found to be (1) linear in the probe intensity, (2) monochromatic, (3) highly efficient (∼3%), (4) approximately equally intense in the Stokes and anti-Stokes, and (5) emitted at angles in agreement with phase-matching conditions. A coupled-wave theory of the scattering is found to account quantitatively for most of the observations. Possible applications for the technique are suggested.