In this paper, the effects of attenuation coefficient and effective gain length on output energy of stimulated Brillouin scattering (SBS) in water are investigated theoretically and experimentally.The experimental results indicate that the smaller the attenuation coefficient, the higher the output energy of SBS is.When the energy of incident laser is very high and the effective gain length is long enough, the SBS may obtain high enough energy thereby reach an extremely strong peak power due to the pulse compression; once it exceeds the threshold of SRS or second - order SBS, the SBS is able to excite an SRS or a second-order SBS as a new source and consumes a part of its own energy.Therefore, the longer the effective gain length, the lower the output energy of SBS is.%本文从理论和实验上分析了水的衰减系数及有效增益长度对受激布里渊散射(SBS)输出能量的影响.实验结果表明,衰减系数越小,SBS输出能量越高.由于脉宽压缩效应,当入射光能量足够高并且有效增益长度相对较长时,SBS易获得高能量而形成极高的峰值功率.一旦这种峰值功率超过受激拉曼散射(SRS)或者二阶SBS阈值,SBS就会作为一个新的激发源去激发SRS或者二阶SBS,从而消耗掉部分SBS的能量,所以会出现后向有效增益长度越长,SBS的输出能量越低的现象.
展开▼
