激光烧蚀CH薄膜特性

Laser transfer in plasma produced by CH foam

报道了神光Ⅱ装置上激光膜相互作用的实验,实验利用能量计和光电管测量激光与CH薄膜作用前后的能量和时间波形的变化。结果表明:激光对CH薄膜透过率由作用产生的激光等离子体电子密度决定;功率密度为1.0×1014 W/cm2的激光与CH薄膜作用下,入射激光能量脉冲前沿与薄膜作用产生激光等离子体;在200ps时,激光等离子体电子密度稀疏到临界密度以下,激光开始透过等离子体;在700ps后,等离子体密度远低于临界密度,激光完全透过激光等离子体。

This paper reports the laser transfer in plasma produced by CH on Shengguang Ⅱ. The laser transmission rate was decided by the plasma density. When the laser incidence was 0.5 gm CH on Shengguang Ⅱ , the plasma density would be un- der critieal value after 200 ps, the laser would pass the plasma. When the plasma density was 1 % critical density after 700 ps, the laser could pass the plasma completely.