激光等离子体相互作用的受激拉曼散射饱和效应

Saturation of stimulated Raman scattering in laser-plasma interaction

在激光等离子体相互作用过程中,受激拉曼散射(SRS)会通过Langmuir波衰减不稳定性(LDI)和电子俘获两种机理饱和.文章给出均匀一维等离子体和低强度非相对论激光作用中,LDI和电子俘获两种机理下的SRS饱和时间的解析表达式.SRS饱和时间与入射激光强度,电子密度,电子温度,初始电子密度微扰等参数有关.解析理论计算得到了与模拟和实验相符的结果.

The saturation of stimulated Raman scattering （SRS） through Langmuir decay instability （LDI） and electron trapping in laser-plasma interaction process is studied. Analytical expressions for the saturation time of SRS are obtained for both the LDI and electron trapping schemes in 1-D homogeneous plasma irradiated by unrelativistic laser beams. The simple analytical model agrees well with numerical simulation and experiment in respect of the dependence of the saturation time of SRS on the parameters of lasers and plasmas.