Threshold reduction of stimulated Brillouin scattering by the enhanced Stokes noise initiation

A method of threshold reduction for stimulated Brillouin scattering (SBS) h as been demonstrated in a SBS medium combined with a laser dye. It is based on the enhanced Stokes noise initiated by additional field with a Brilloui n-shifted frequency component emitted from the laser dye in the SBS medium. Rhodamine 6G dye dissolved in SBS medium (ethanol), which was pumped by a 570 nm wavelength laser, was used to prove the SBS threshold reduction by t he additional Stokes fields. The SBS threshold of this solution was reduced to a level about four times lower than that of the pure SBS medium. Also, the experimental results were investigated using the modified formula for t he SBS threshold. (C) 1999 American Institute of Physics. [S0003-6951(99)03 110-1].