超短超强激光在稀薄等离子体中的自聚焦传输

Self-focusing propagation of ultra-short ultra-intense laser in under-dense plasmas

开展超短超强激光与次稠密等离子体相互作用实验,采用探针光对激光等离子体相互作用区域进行阴影成像,研究了不同激光功率与临界功率比值及不同激光脉冲长度与等离子体波波长比值下的激光在次稠密等离子体中的自聚焦传输。结果表明:相对论效应是超短脉冲在次稠密等离子体中的主要自聚焦机制,激光功率与临界功率比值是影响超短脉冲在次稠密等离子体中形成自聚焦的关键条件。

Experiments have been performed using ultra-short (30 fs) ultra-intense laser pulse(up to 1018 W/cm2) focused into under-dense plasmas. A probe pulse was used for the shadowgraphy and the investigation on the propagation of laser under various conditions was presented. The results demonstrate that relativistic effect is the main self-focusing regime and the ratio of laser power to critical power is the key condition for self-focusing of the ultra-short ultra-intense laser in under-dense plasmas.