Stimulated Brillouin scattering phase-conjugated wave reflection from fused-silica glass without laser-induced damage

The stimulated Brillouin scattering (SBS) reflectivity of bulk fused-silica glass is measured at the wavelength of 1.06 mm. At long pulse pumping using a longer focusing lens, a fused-silica glass shows high SBS reflectivity of approximately over 95% with no damage observation at a pumping energy of 380 mJ in a pulse duration of 15 ns. We have found that the laser-induced damage threshold at a high SBS reflectance condition is due to reduction of the transmitted power to focus. This makes it possible to operate with high performance in all solid state lasers using a phase-conjugated mirror with fused-silica glass.