强激光在磁化等离子体中的调制不稳定性

核聚变与等离子体物理 ›› 2010, Vol. 30 ›› Issue (4): 301-305.

强激光在磁化等离子体中的调制不稳定性

陈华英，刘三秋，李晓卿

(1. 南昌大学材料学院，南昌 330031；2. 南昌大学理学院，南昌 330031；3. 南京师范大学物理系，南京 210097)

收稿日期:2010-04-24 修回日期:2010-10-03 出版日期:2010-12-15 发布日期:2011-01-26
作者简介:陈华英(1979-)，女，江西南昌人，博士研究生，讲师，研究方向为激光等离子体。
基金资助:
中国科学技术部国际科技合作项目(2009DFA02320)；国家自然科学基金(地区)资助项目(10963002)

Modulational instability of intense laser beam in magnetized plasma

CHEN Hua-ying, LIU San-qiu, LI Xiao-qing

(1. College of material, Nanchang University, Nanchang 330031; 2. College of Science, Nanchang University, Nanchang 330031; 3. Department of Physics, Nanjing Normal University, Nanjing 210097)

Received:2010-04-24 Revised:2010-10-03 Online:2010-12-15 Published:2011-01-26

摘要/Abstract

摘要：

采用洛伦兹变换推导出左旋椭圆偏振强激光在磁化等离子体中的非线性色散关系，根据Karpman方法推导出激光场包络的非线性控制方程，分析了在磁化等离子体中左旋椭圆偏振激光的调制不稳定性，得到了调制不稳定的时间增长率。分析结果表明，磁化等离子体中自调制不稳定的极大增长率较非磁化情况明显减小，且在激光等离子体临界面附近处调制不稳定性的时间增长率显著增大。

关键词: 磁化等离子体, 左旋椭圆偏振激光, 调制不稳定性, 非线性色散关系

Abstract:

The nonlinear dispersion relation is derived for an intense left-hand elliptically polarized laser beam propagating through magnetized plasma by means of the Lorentz transformation. In terms of the Karpman method, the nonlinear governing equation for the envelope of the laser field is obtained. The modulational instability of the intense left-hand elliptically polarized laser beam in magnetized plasma is analyzed and the temporal growth rate of modulational instability is found. The analysis shows that the maximum growth rate of self-modulation instability is obviously smaller for magnetized plasma compared to the unmagnetized case. It is also shown that the temporal growth rate of modulational instability is increased significantly near the critical surface in a laser-plasma.

Key words: Magnetized plasma, Left-hand elliptically polarized laser beam, Modulation instability, Nonlinear dispersion relation

中图分类号:

O437

陈华英，刘三秋，李晓卿. 强激光在磁化等离子体中的调制不稳定性[J]. 核聚变与等离子体物理, 2010, 30(4): 301-305.

CHEN Hua-ying, LIU San-qiu, LI Xiao-qing. Modulational instability of intense laser beam in magnetized plasma[J]. NUCLEAR FUSION AND PLASMA PHYSICS, 2010, 30(4): 301-305.

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