KrF激光受激布里渊散射反射率稳定性的研究

A study on the stability of stimulated Brillouin scattering for KrF laser

实验研究发现抽运功率密度 (或抽运能量 )的波动引起的受激布里渊散射 (SBS)反射率的不稳定程度受实验参数 (抽运能量、介质气压和透镜焦距 )的影响 .当抽运能量、介质气压和透镜焦距这三个参数同时满足下列条件时可以获得稳定的输出 :抽运能量超过 5倍的SBS阈值 ,介质气压在 16× 10 5Pa和透镜焦距在 15— 5 0cm的范围内 ;同时还发现当改变实验参数时SBS反射率与稳定性的变化规律完全一致 ,反射率越高稳定性越好 .通过理论分析得到SBS反射率的相对稳定度实际上是受GIL因子的影响 。

The stability of reflectivity of stimulated Brillouin scattering(SBS) for KrF laser, which is caused by the fluctuation of pump power density, depends on experimental parameters including the pump energy, pressure of the medium and focal length. The stable SBS output can be obtained when the following conditions are satisfied: the pump energy exceeds 5 times the threshold energy, the SF6 pressure is 16 x 10(5) Pa and the focal length is within 15-50cm. It is also discovered that the stability of SBS reflectivity is increased with the SBS reflectivity. The stability of SBS reflectivity is in fact determined by GIL. The theoretical calculation results are consistent with the experimental results.