反射光中Stokes成分对受激布里渊散射过程的影响

Influence of Stokes component in reflected light on stimulated Brillouin scattering process

区别于传统的受激布里渊散射 (SBS)发生器和放大器 ,提出了一种新型的SBS模型 :自供种子光模型 (selfstokesseeding ,SSS) .通过对抽运光波形函数的傅里叶变换得到了Stokes成分在抽运光中所占的比例 ,即Stokes能量比 .考虑SSS效应 ,数值求解了SSS耦合波方程组 ,得到了SBS反射率的时间演变形式 ,理论研究发现 ,当抽运光正入射到平板样品上时 ,反射光中的Stokes成分极大地促进了SBS起振过程 ,其结果相当于反向注入一定强度的种子光 。

A new stimulated Brillouin scattering (SBS) configuration, SSS(Self Stokes Seeding), is presented to describe the influence of Stokes component in a pump light on SBS process. The fast Fourier transform is used to calculate the Stokes energy ratio which denotes the ratio of the energy of Stokes component to that of total pump laser. The coupled SBS equations is solved numerically and the SSS effects is evaluated. The study shows that when the pump laser is reflected normally by the back surface of the flat sample, the Stokes component plays an important role in SBS process, such as decreasing the initiation duration. The larger the Stokes energy ratio is, the shorter the initiation duration is.