Compton散射下超强激光等离子体通道的演化  

Channel evolution of extra-intense laser plasma under Compton scattering

作　　者：欧群雍 郝东山 

机构地区：[1]郑州工业应用技术学院信息工程学院,新郑451150

出　　处：《原子与分子物理学报》2016年第3期482-487,共6页Journal of Atomic and Molecular Physics

基　　金：河南省基础与前沿技术研究资助项目(142300410283);河南省教育厅科学技术研究重点项目(12B520063)

摘　　要：应用多光子非线性Compton散射模型、空间动态补偿模型、非线性薛定谔方程和数值模拟方法,研究了Compton散射对超强飞秒激光等离子体中通道的影响,提出了将Compton散射光作为形成等离子体通道的新机制,给出了超强飞秒激光脉冲在等离子体中传播和电子密度随时间变化的非线性修正方程,并进行了数值模拟.研究发现:散射使等离子体中电子密度峰值增大1个量级,半径增大1 mm.激光最大功率密度被限制在10^(18)W/m^2以下,随传输距离增大缓慢衰减.传输初始阶段,单脉冲衰减能量较散射前增大2%,之后衰减较平缓.通过增加超强飞秒激光脉冲输入功率,能有效地增加电子密度峰值,有利于等离子体通道的形成.并对所的结论给出了初步物理解释.By using the model of multi - photon nonlinear Compton scattering, the model of space dynamic compensation, nonlinear Schrodinger equation and numerical simulation means, the influence of the channel in the extra- intense femo- second laser- plasma produced by Compton scattering was studied. A new mechanism of the plasma channel formed by Compton scattering optical was given. The nonlinear amended equations on the propagation of the extra - intense femo - second laser pulse in the plasma and the change of the electron density along time were given out, and the equations were simulated with the values. The results show that the one order of magnitude of the crest value of the electron density in the plasma is increased by Compton scattering than that before the scattering, and the 1 mm creased number of the radius is produced. The maximum laser power density is limited under 10^18 W/m^2, and it was slowly decreased along the increasing propagation distance. The 2% decreased energy of the simple pulse is produced than the scattering in the initial propagation stage, and after, the decrease is mild. The crest value of the electron density is affectively increased through the increase of the import power of the extra - intense femo - second laser pulse, and the means is good to the forming of plasma channel. Then, the initial physics explanations on the results are given out.

关 键 词：等离子体 超强飞秒激光 等离子体通道 电子密度峰值 自聚焦 非线性Compton散射 

分 类 号：O53[理学—等离子体物理] O437[理学—物理]