受激热散射与布里渊散射的竞争及其共轭特性

研究了因掺杂硝酸铜而具有不同吸收系数的丙酮液体作为主振荡功率放大(MOPA)系统相位共轭镜时．液体中受激热散射(STS)与受激布里渊散射(SBS)之间的竞争及其相位共轭输出特性。结果显示．随着吸收系数的增加．受激热瑞利散射(STRS)将抑制受激布里渊散射或受激热布里渊散射(STBS)而成为主导过程．且其增益随着吸收系数的增加而增加．能量相对起伏随着吸收系数的增加而降低：由于阈值效应．弱抽运时受激热瑞利散射与受激布里渊散射一样将丢失原始波前中较弱的相位信息：在适当的吸收系数和抽运条件下利用吸收液体中的受激热瑞利散射获得高品质相位共轭是完全可能的。

Competition between Stimulated Thermal and Briilouin Scattering and Its Phase Conjugation Characteristic

It was experimentally investigated that competition between stimulated thermal scattering (STS) and stimulated Brillouin scattering (SBS) in absorbing liquids and that its phase conjugation characteristic in a master oscillator power amplifier (MOPA) system with a cell containing acetone dyed with small amounts of Cu(NO 3) 2 served as phase-conjugation mirror. It was showed that the stimulated thermal Rayleigh scattering (STRS) would predominate over the stimulated Brillouin scattering or stimulated thermal Brillouin scattering (STBS) by increasing the absorption coefficient of acetone, the gain of the stimulated thermal Rayleigh scattering increased and relative fluctuation of the output energy decreased with the absorption coefficient increased;under weaker pumping conditions stimulated thermal Rayleigh scattering would loss weaker phase information in original wavefront as same as stimulated Brillouin scattering did due to threshold effect; it is really possible to obtain high-quality phase conjugation by stimulated thermal Rayleigh scattering in absorbing liquid with appreciable absorption coefficient under appreciable pumping conditions.