圆偏振激光在强磁化高密度等离子体中的传输和能量吸收

Early studies on laser and magnetized plasma interaction focus on B < 1 (B = wc / w is the normalized external magnetic field. wc and w are the electron cyclotron frequency and the laser frequency). Transmission and absorption of the laser are limited to the cutoff density. In recent years the development of technology has made strong magnetic field B> 1 available and observed in recent experiments. Under action of such strong magnetic field, there is no cutoff density for a right-handed circularly polarized laser. It can propagate in any high-density plasma until the energy completely deposit. Therefore, B>1 will change the behavior of right-handed circularly polarized laser. In this project, we intends to build a theoretical model of laser and strong magnetic high density plasma interaction, with numerical simulation method, focusing on (B>1) (1) The non-relativistic pulse propagation in the strongly magnetized high-density plasma. Obtain the laser pulse energy conversion efficiency to the plasma; (2) Extend to relativistic laser pulses, study the laser energy deposition and high-energy particle beam production. (3) Transportation of high-quality electron beam in a strongly magnetized high-density plasma. The new physical phenomena studied in this project will provide new ideas for laser fusion ignition.

早期的激光与磁化等离子体相互作用研究集中在B<1的范畴(B=wc/w为归一化的外加磁场强度。wc和w为电子回旋频率和激光频率)，激光的传输与吸收局限在截止密度以下的区域。近年来强磁场技术的发展使B>1的磁场成为可能并在近期实验中观测到。在这样的强磁场作用下，右旋圆偏振光不再有截止密度，它可以在任意高密度的等离子体中传输直至能量完全沉积。因此，B>1的超强磁场将使右旋圆偏振激光在等离子体中的行为发生根本变化。鉴于此，本项目拟建立激光与强磁化高密度等离子体相互作用的理论模型，结合数值模拟的方法，针对B>1的情况，重点研究（1）非相对论长脉冲在强磁化高密度等离子体中的传输机制。获得激光脉冲能量到等离子体的转换效率；（2）拓展到相对论激光，研究激光脉冲的能量沉积及高能粒子束的产生。（3）高质量电子束在强磁化高密度等离子体中的传输及加热机制。本项目研究的全新的物理现象将为激光聚变点火提供新的思路。

早期的激光与磁化等离子体相互作用研究集中在B<1的范畴(B=Wc/W为归一化的外加磁场强度。Wc和W为电子回旋频率和激光频率)，激光的传输与吸收局限在截止密度以下的区域。近年来强磁场技术的发展使B>1的磁场成为可能并在近期实验中观测到。在这样的强磁场作用下，许多物理现象和机制会发生改变。基于此，本项目提出了激光与强磁化高密度等离子体相互作用的理论模型，结合数值模拟的方法，针对B>1的情况，重点研究了（1）非相对论长脉冲在强磁化高密度等离子体中的传输机制。获得了激光脉冲能量到等离子体的转换效率；（2）拓展到相对论激光，研究了激光脉冲的能量沉积；（3）研究了强磁化等离子体中阿秒电子片的产生；受强磁场发展的限制，本项目增加了（4）相对论激光脉冲与固体靶等离子体相互作用中的电子加速问题。