Compton散射下超强激光瞬态等离子体的频率响应特性  

Frequency response characteristics of transient-plasma of extra-intense laser under Compton scattering

作　　者：毛建景 张凯萍 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》2015年第6期1008-1012,共5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(092300410227)

摘　　要：应用多光子非线性Compton散射和实验探测的方法,对超强激光瞬态等离子体的频率响应特性进行了研究,提出了将入射超强激光和Compton散射光作为形成等离子体碰撞频率的新机制,给出了电子碰撞频率的时空演化方程和实验结果 .结果表明：与散射前相比,4.17 k Hz以下的功率谱线较平滑,不同时刻抖动幅度不大,且抖动的频率降低了1.63 k Hz.当频率达到6.12 k Hz时,功率谱线出现了35 m W幅度抖动,且大幅抖动的频率降低了0.88 k Hz,幅度增大了5 m W.当频率达到9.7 k Hz时,功率谱线的峰值近似于全谱峰值,且该谱线峰值的频率降低了1.3 k Hz.由4.17～9.7 k Hz低频谱产生的功率谱线缩小了0.21k Hz.超过9.1 k Hz后,功率谱线抖动对功率谱线峰值的贡献是次要的.这主要是由于散射使等离子体的高频非线性成分增大,低频成分缩小,且4.17～9.7 k Hz中亦包含有散射贡献的缘故.By using multi- photon nonlinear Compton scattering model and the means of experimental detection,the frequency response characteristics of transient- plasma of extra- intense laser were studied. A new mechanism on plasma impact frequency formed by the incident extra- intense laser and Compton scattering light was given,and the time and space evolution equation and experimental results on the electric impact frequency was given out.The results show that the power spectrum line under 4. 17 k Hz is milder than that before the scattering,the different time shaking extents are not big,and 1. 63 k Hz shaking frequencies are decreased. When the frequency is 6. 12 k Hz,a 35 m W shaking extent is produced in the power spectrum line,and 0. 88 k Hz shaking extent frequency is decreased,and 5 m W peak value is increased. When frequency is 9. 7 k Hz,the peak value of power spectrum line and all spectrum line peak values are almost matching,and 1. 3 k Hz frequency of the spectrum line peak value is decreased. 0. 21 k Hz power spectrum line produced by 4. 17 ～ 9. 7 k Hz frequency spectrum is decreased. Over 9. 7k Hz,the contribution on the power spectrum line shaking to the power spectrum line peak value is secondary. The causes may be that the high frequency nonlinear composition of plasma is increased by the scattering,the low frequency composition is decreased,and also there is the scattering contribution in 4. 17 ～ 9. 7 k Hz.

关 键 词：超强激光 瞬态等离子体 频率响应 功率谱线 多光子非线性COMPTON散射 

分 类 号：O383[理学—流体力学] O531[理学—力学]