宽带KrF激光泵浦SBS的研究

 理论和实验研究了宽带（15GHz）KrF激光泵浦的受激布里渊散射（SBS）在SF₆介质中的转换效率和脉宽压缩比的规律。介质在1.6MPa、透镜焦距为15cm和30cm时，测得SBS最大反射率分别为40%和45%，当泵浦能量大于60mJ时SBS反射率开始趋于平坦；介质在0.85MPa、透镜焦距在30cm时，SBS脉宽压缩比随泵浦能量的上升而下降，最大压缩比为5。建立了宽带多模KrF激光泵浦的SBS理论模型，假设宽带KrF激光光谱谱线由若干窄带谱线组成，这些窄带谱线之间在产生SBS过程中有一定程度的耦合。给出了理论模型结果，并与实验结果进行了比较。

Investigation of SBS pumped with a broadband KrF laser

The characteristics of stimulated Brillouin scattering reflectivity and pulse compression ratio for broadband (15GHz) KrF laser radiation pump in SF 6 gas are investigated numerically and experimentally in this paper. It has obtained that a peak reflectivity of 40% and 45% has been measured at 1.6MPa with lenses of focal length 15cm and 30cm, respectively, and a saturated region of SBS reflectivity is discovered at pump energy above 60mJ. SBS pulse compression ratio decreases with pump energy at 0.85MPa.and the maximum of pulse compression ration measured is 5. SBS numerical mode for a broadband multimode KrF laser pump has been built up in this paper. The basic premises of the mode are that SBS arises from each laser line with coupling to some extent. In this paper numerical results have been obtained and are compared to experimental results.