强激光与粒子束, 2004, 16 (7): 870, 网络出版: 2006-05-15
强激光场作用下部分离化等离子体的非线性极化
Nonlinear polarization of partially stripped plasmas in intense laser field
强激光场 部分离化等离子体 束缚电子 非线性极化 Intense laser field Partially stripped plasmas Bound electron Nonlinear polarization
摘要
针对线偏振光场,提出一个原子极化模型.假设原子核为静止不动的正电背景,束缚电子不发生再电离,自由电子与离子也不发生复合,电子对电场的响应是瞬时的,并用旋转椭球来近似描述电子云的形状.通过此模型,可解析地计算出不同电离状态原子的第1阶线性和第3阶非线性极化率、相应的极化电流、以及极化介质(原子)的折射系数.在低场近似下,这些结果可自洽地过渡到传统的非简谐振子模型,并可得到对应的谐振子的固有频率和非线性系数.
Abstract
A physical model of partially ionized high-Z atoms in an intense laser field is presented, in which a spheroid distribution for the electron cloud (bound electron) surrounding the nucleus is assumed. The first and the third susceptibilities, as well as the nonlinear polarization current and the refractive index, are analytically obtained by this model. At low laser field limit, these results are consistent with that obtained from the traditional non-harmonic oscillator model, nay, the corresponding characteristic frequency of oscillator and the nonlinear coefficient can be found self-consistently from the presented model.
胡强林, 刘世炳, 马善钧. 强激光场作用下部分离化等离子体的非线性极化[J]. 强激光与粒子束, 2004, 16(7): 870. HU Qiang-lin, LIU Shi-bing, MA Shan-jun. Nonlinear polarization of partially stripped plasmas in intense laser field[J]. High Power Laser and Particle Beams, 2004, 16(7): 870.