飞秒激光与固体靶相互作用中光辐射时间特性的实验研究  

Experimental study of time characteristic of optical radiation in femtosecond laser interaction with solid targets

作　　者：王光昶[1] 马春生[2] 张建炜[1] 白春燕[2] 刘玉红[1] 郑志坚[3] 

机构地区：[1]成都医学院物理教研室,成都610083 [2]云南思茅师范高等专科学校计科系,普洱665000 [3]中国工程物理研究院激光聚变研究中心,绵阳621900

出　　处：《物理学报》2012年第9期347-353,共7页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:10876039);云南省教育厅科学研究基金(批准号:2010Y444);四川省教育厅重点项目科研基金(批准号:11ZA203)资助的课题~~

摘　　要：为了探索光辐射的时间特性,在100 TW掺钛蓝宝石飞秒激光器上利用光学条纹相机,分别在靶背表面法线方向测量了光辐射的时间积分和时间分辨成像光斑.实验测量结果显示:光辐射时间积分成像光斑呈长条状,而辐射区域有发散角、有光强分布,包含多种辐射成分;光辐射的时间分辨成像光斑进一步证明,渡越辐射(TR)是信号强而快,持续时间短,为皮秒(ps)量级,是最先到达屏幕上,并推算出相应的持续时间为85.5ps.其他成分光辐射是信号弱而慢,持续时间长,为纳秒(ns)量级,是最后到达屏幕上.光辐射的时间特性能为鉴别和判断TR信号提供了新的依据.In this paper, the time-integrated image pattern of spatial distribution and time-resolved image of optical radiation are measured in the normal direction from the rear side of targets by employing optical streak camera on the 100 TW femtosecond laser facility. The image pattern of spatial distribution presents a strip-shape： the region of optical radiation has a radiation angle and optical intensity distribution, and contains various components; the time-resolved image of optical radiation presents the time-resolved pattern of the optical radiation, witch further proves that the transition radiation is intense, which has short duration （ps） and correspouns to duration of TR of 85.5 ps. and other optical radiations are weak, which have very long duration （ns）. The time-resolved characteristic of optical radiation can provide new evidence for discrimination and judgement of TR.

关 键 词：飞秒激光 光辐射 时间特性 渡越辐射 

分 类 号：O53[理学—等离子体物理]