利用一维(1D3V)、显式、全电磁、相对论粒子模拟代码研究动理学范畴内激光与等离子体相互作用中的受激拉曼散射，给出了粒子代码的控制方程及其数值离散的详细方案。研究表明：动理学效应在受激拉曼散射不稳定性中十分重要；时间平均的反射率在阈值强度处跃升，在更高的激光强度处达到饱和；受激拉曼背向散射周期性地在次皮秒内爆发，离子效应延迟背向拉曼散射的发生；电子俘获导致了背向拉曼散射出现爆发；Langmuir波的非线性频移使得背向散射达到饱和。%Stimulated Raman scatting (SRS), which is one of the parametric processes of laser-plasma interactions, is examined by an explicit, electromagnetic, relativistic kinetic particle-in-cell code in one dimension. The code algorithm and implementation details are discussed. It is found that kinetic effects are important to SRS instability. Time-averaged reflectivity onsets at threshold intensity, and saturates at higher intensity. Backward SRS bursts in sub-picosecond, periodically. Kinetic ions initially delay the growth of SRS. Electron trapping results in the SRS bursts. The saturation of SRS results from the nonlinear frequency shift of Langmuir wave. Work is underway to add binary Coulomb collision to parallelize it, and to extend the code to 2D3V.
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