飞秒激光-固体靶相互作用中超热电子能量分布的实验研究  

Experimental study on energy distribution of the hot electrons generated by femtosecond laser interacting with solid targets

作　　者：谷渝秋[1] 蔡达锋[1] 郑志坚[1] 杨向东[2] 周维民[1] 焦春晔[1] 陈豪[1] 温天舒[1] 淳于书泰[1] 

机构地区：[1]中国工程物理研究院激光聚变研究中心,绵阳621900 [2]四川大学原子分子物理研究所,成都610065

出　　处：《物理学报》2005年第1期186-191,共6页Acta Physica Sinica

基　　金：中国工程物理研究院基金重大项目(批准号 :2 0 0 0Z0 2 0 6);国家自然科学基金 (批准号:10 2 75 0 5 6)资助的课题~~

摘　　要：用 3TW飞秒激光器研究了激光 固体靶相互作用中产生的超热电子的能量分布 .超热电子构成各向异性的能量分布 :在靶法线方向 ,超热电子能谱呈类麦克斯韦分布 ,拟合的温度约为 2 0 6keV ,该方向占主导地位的加速机理是共振吸收 ;在激光反射方向 ,超热电子能谱先是出现一个局部的平台 ,然后逐渐衰减 ,呈现非类麦克斯韦分布 ,这是由于几种加热机理共同作用的结果 ,其中占主导地位的是反射激光对电子的加速 .在靶法线方向超热电子的温度和产额均大于激光反射方向超热电子的温度和产额 。This paper reports the results of the experiment of hot electron energy distribution during the femtosecond laser-solid target interaction. The hot electrons formed an anisotropic energy distribution. In the direction of the target normal, the energy spectrum of the hot electron was a Maxwellian-like distribution with an effective temperature of 206keV, which was due to the resonance absorption. In the direction of the specular reflection of laser, there appeared a local plateau of hot electron energy spectrum at the beginning and then it was decreased gradually, which maybe produced by several acceleration mechanisms. The effective temperature and the yield of hot electrons in the direction of the target normal is larger than those in the direction of the specular reflection of laser, which proves that the resonance absorption mechanism is more effective than others.

关 键 词：超热电子 固体靶 共振吸收 能谱 法线 能量分布 相互作用 麦克斯韦分布 飞秒激光器 衰减 

分 类 号：TN24[电子电信—物理电子学]