Stimulated Raman-Kerr scattering from a benzene liquid-core fiber system

Broadening of stimulated Raman scattering (SRS) lines from organic liquids that has been reported previously can not be explained by the existing theories. The spectral distributions of the transmitted pump line first- and second-order SRS lines (with a 992-cm^-1 Raman shift) are reported here for a benzene-liquid-filled, multimode, hollow quartz-glass fiber. The following features are observed: (1) The broadening of the pump line is nearly negligible except for a very high pump level. (2) The broadening of the first-order Stokes (S₁ ) SRS line is prominent even for lower pump levels. (3) The broadening of the second-order Stokes (S₂ ) line is much stronger and wider than that of the S₁ line at the same pump level. It is suggested that the main mechanism responsible for these features is the Raman-induced stimulated reorientation scattering of the anisotropic benzene molecules.