拍瓦激光驱动纳米刷靶高品质质子束的产生

Generation of high-quality proton beam in nanobrush targetsdriven by PW laser pulse

超强激光加速产生的高能质子束源在基础物理研究、材料科学、生物医疗等领域具有广泛应用前景。基于激光聚变研究中心的SILEX-II装置,开展了高对比度飞秒激光驱动纳米刷靶质子加速实验研究。采用等离子体镜技术进一步提升激光对比度,有效降低了预脉冲对纳米刷靶结构的影响。相比于平面靶,采用纳米刷靶质子截止能量提高到1.5倍,质子束产额增加近一个量级,成功验证了超高功率密度下纳米刷靶对激光离子加速的增强效果,并且有效提升了质子束空间分布的均匀性。研究结果为高品质质子束源的产生和应用提供了技术途径。

High-energy proton beam sources produced by ultra-intense laser acceleration have wide applicationprospects in basic physics,materials science,biomedical research and other fields.Based on SILEX-II device of LaserFusion Research Center,the experimental studies on proton acceleration of nanobrush targets driven by high-contrastfemtosecond PW laser pulse have been carried out.Plasma mirror technology was used to further improve the lasercontrast,which effectively reduces the influence of pre-pulse on the structure of the nanobrush target.Compared withplanar target,the proton cut-off energy of nanobrush targets increased to 1.5 times,and the proton beam yieldincreased by nearly one order of magnitude.This successfully verifies the enhancement of nanobrush targets on laserion acceleration at ultra-high power density,and the improved uniformity of the proton beam spatial distribution.These results provide a technical way for the generation and application of high-quality proton beam sources.