Nd:YAG四倍频激光抽运D_2和D_2／He受激拉曼散射的实验研究

Experimental investigations of stimulated Raman scattering in D_2 and D-2/He pumped by the Nd:YAG fourth harmonic laser

使用脉冲Nd:YAG四倍频激光抽运充有纯D2气体和D2／He混合气体的拉曼池。实验研究了受激拉曼散射的能量转换效率和能量稳定性与系统主要参量,包括抽运光能量、D2气体压强和加入惰性气体 He的关系。实验表明,适量惰性气体He的加入在没有降低一阶斯托克斯散射光(S1,波长:289．04nm)能量稳定性的前提下,有利于提高其能量转换效率,最大能量转换效率达到22．1％。通过实验分析,得到了受激拉曼散射一阶斯托克斯散射光的能量转化效率和能量稳定性的优化条件。

The fourth harmonic of a pulsed Nd：YAG laser is used to pump Raman cells filled with D2 and D2/He. The influence of the systemic parameters, such as the pump energy, pressure of pure D2, and addition of He into D2/He, on the energy conversion efficiencies and energy stability of stimulated Raman scattering radiations, have been experimentally studied. It is proved that the energy conversion efficiency and energy stability of S1 is influenced by the intensity and energy stability of pump laser and the pressure of gas medium in Raman cell. On the premise of not lowering the energy stability of the first Stokes radiation （S1, 289.04 nm）, it is propitious to increase the energy conversion efficiency of S1 to add proper ratio of He into Raman cell filled with D2. The maximum energy conversion efficiency of S1 reaches 22.1% in D2/He. By experimental analysis, the conditions for optimizing the energy conversion efficiency and energy stability of S1 have been gotten.