强激光与柱腔靶作用下准直高能电子束的产生  

High-energy collimated electron acceleration from ultra-intense laser interaction with tube targets

作　　者：何武[1,2] 周维民[2] 张智猛[2] 矫金龙 单连强[2] 蒋刚[1,3] 

机构地区：[1]四川大学物理科学与技术学院,成都610064 [2]中国工程物理研究院激光聚变研究中心,等离子体物理重点实验室,四川绵阳621900 [3]四川大学高能量密度物理教育部重点实验室,成都610064

出　　处：《强激光与粒子束》2015年第7期92-96,共5页High Power Laser and Particle Beams

基　　金：国家自然科学基金项目(11474208,11175165)

摘　　要：利用二维PIC粒子模拟程序研究了超短超强激光脉冲与柱腔靶相互作用产生的表面超热电子加速现象。采用光强为1021 W/cm2量级的超高斯激光脉冲掠入射进入柱腔靶,在靶的内壁上观察到了GeV量级的表面超热电子。超热电子束被准静态的电场和磁场约束在内壁表面附近,保证了电子束的准直性,发散角仅为1.6°;并且由于超热电子束在纵向激光电场中加速了mm级的距离,激光到高能电子(>100 MeV)的转换效率达到了26.6%。另外,通过多参数模拟和理论解析讨论了激光的光强以及横向空间分布对这种表面超热电子加速的影响。Two dimensional PIC （ particle in cell） simulation is used to investigate the interaction between ultra intense short pulse lasers with tube targets. When an ultra intense super Gaussian laser pulse propagates at a grazing incidence angle into the tube target, GeV class electron acceleration is observed on the inner surface. Fast electrons are confined along the surface by quasistatic electric and magnetic fields, resulting in a small divergence angle of the generated electron beam. These surface fast e lectrons can be accelerated for a long distance along the tube; as a result, the energy conversion efficiency is very high. The influ ence of the laser intensity and the transverse profile on the surface electron acceleration process is also discussed in the article.

关 键 词：超强激光 柱腔靶 PIC模拟 准直超热电子 准静态磁场 表面电子加速 

分 类 号：O434.12[机械工程—光学工程]