超薄靶激光质子加速实验研究  

Experimental study of laser-driven proton acceleration with ultrathin targets

作　　者：李勇[1,2] 洪伟[2] 吴玉迟[2] 朱斌[2] 何颖玲[2] 赵宗清[2] 胡峰[2] 滕建[2] 刘东晓[2] 詹夏宇[2] 谷渝秋[2] 王晓方[1] 

机构地区：[1]中国科学技术大学近代物理系,中国科学院基础等离子体物理重点实验室,合肥230026 [2]中国工程物理研究院激光聚变研究中心,四川绵阳621900

出　　处：《强激光与粒子束》2010年第5期1001-1004,共4页High Power Laser and Particle Beams

基　　金：国家自然科学基金项目(10775121,10774133,10876039);等离子体物理国家级重点实验室基金项目(9140C6802030603);中国科学院创新项目

摘　　要：在超短超强飞秒SILEX-Ⅰ激光装置上,开展了薄膜靶激光质子加速的实验研究。实验发现激光预脉冲、靶厚度对质子加速有很大的影响。在激光强度3×10^18-3×10^19W/cm^2条件下,采用前表面厚度为3μm铜、后表面镀4μm厚CH靶,质子的最大能量达到3.15 MeV。而对190 nm厚CH膜靶,质子的最大能量为0.54 MeV。初步研究了激光偏振对质子加速的影响,相同激光功率条件下,圆偏振激光加速产生的质子最大能量略低于P偏振打靶。这些结果与靶后鞘层加速机制相一致。The generation of proton beams from thin-foil targets on SILEX-Ⅰ is studied.It shows that prepulse has a profound effect on the maximum proton energy.The thinner the target is,the more sensitive it is to the prepulse.Under the laser intensity of 3×10^18 to 3×10^19 W/cm^2,the maximum proton energy is 0.54 MeV with 190 nm CH target and 3.15 MeV with 3 μm Cu target（back surface plated with 4 μm CH） respectively.Besides,the effect of laser polarization on proton acceleration is also studied.The maximum proton energy accelerated by a circularly polarized laser pulse is a little lower than that by a P-polarized laser pulse with the same laser power density.The mechanism is consistent with target normal sheath acceleration.

关 键 词：质子加速 靶背法向鞘层加速 截止能量 圆偏振 飞秒激光 

分 类 号：O434.12[机械工程—光学工程] TL65[理学—光学]