Compton散射对等离子体零色散附近调制不稳定性的影响  

Influence of Compton Scattering on Modulation Instability Near Zero Dispersion in Plasma

作　　者：郝东山[1] 朱江波[1] 

机构地区：[1]郑州华信学院信息工程系,河南新郑451150

出　　处：《光子学报》2014年第10期216-220,共5页Acta Photonica Sinica

基　　金：河南省基础与前沿技术研究项目(No.092300410227)资助

摘　　要：应用Compton散射模型和非线性Schrdinger方程,研究了Compton散射对等离子体零色散附近调制不稳定性的影响,提出了将Compton散射作为形成调制不稳定性的新机制,给出了等离子体修正色散方程,并进行了数值计算.结果表明:二阶色散较大时,远离零色散附近调制不稳定性增益谱由入射和散射光产生的二阶色散决定,随二阶色散增大,四阶色散作用迅速减小,这是因散射效应有效削弱了四阶效应的缘故.零色散附近调制不稳定性增益谱由入射和散射光产生的四阶色散决定,二阶色散被湮灭,微扰频率最大值向临界微扰频率较快靠近,这是因散射效应有效增强了四阶效应的缘故.增益谱宽随等离子体损耗增大而迅速增大,这是因功率增大使散射效应增强,导致带电粒子辐射阻尼增强的缘故.The influence of Compton scattering on the modulation instability near zero dispersion in plasma is studied by using the model of multi-photon nonlinear Compton scattering and nonlinear Schrdinger′s equation,a new mechanism on the modulation instability is formed by Compton scattering has been raised,a amended dispersion equation on the light pulse propagation has been given out,and it is simulated with the numbers.The results show that when the second-step dispersion is bigger,the gain score of the modulation instability of the wander from the nearby zero dispersion is decided by the secondstep dispersion produced by incident and scattered lights.The fourth-step dispersion effect is quickly decreased along with the increasing of the second-step dispersion,and the cause is that the fourth-step dispersion effect is affectively weakened by Compton scattering.The gain score of the modulation instability near the zero dispersion is decided by the fourth-step dispersion produced by incident light and scattered light,the second-step dispersion is annihilated,the maximum number of the perturbation frequency is quickly approached to critical perturbation frequency,and the cause is that the fourth-step dispersion effect is affectively increased by Compton scattering.The width of the gain score is quickly increased along with the increasing of the plasma loss,the cause is that the scattered effect is increased along with the power increasing,and the effect causes that the radiation damping of the charged particle is increased.

关 键 词：等离子体 非线性光学 数值计算 调制不稳定性 色散 耦合 多光子非线性COMPTON散射 

分 类 号：O436.3[机械工程—光学工程]