2 ns, 351 nm激光黑腔靶受激Raman散射实验研究

 介绍了在神光Ⅱ装置上开展的长脉冲2 ns,351 nm激光与黑腔靶相互作用的实验，报道了受激Raman散射光时间分辨谱图及能量测量的实验结果。长脉冲2 ns激光注入小腔靶（Ø700 mm×1 250 mm）时，激光辐照缝靶产生的SRS光能量是激光与全腔靶作用产生的SRS光能量的1.3倍。在2 ns激光与不同尺寸黑腔靶作用的情况下，激光辐照小腔靶产生的SRS光能量比标准腔靶(Ø800 mm×1 350 mm)产生的SRS光能量高1.6倍。由于激光功率密度下降，2 ns激光打靶SRS散射光要弱于短脉冲1 ns激光打靶，但持续时间稍长。实验结果表明：长脉冲2 ns激光与标准腔靶相互作用时，等离子体“堵腔效应”比较严重，标准腔靶尺寸不再合适。

Stimulated Raman scattering from interaction of 2 ns, 351 nm laser with hohlraum

An experiment of laser-plasma interaction in hohlraum plasmas produced by laser beams with 351 nm wavelength, 2 ns pulse duration at SGII laser facility was reported in this paper. The time-resolved spectra and energy of scattered light by stimulated Raman scattering (SRS) were measured. When 2 ns laser entered into a small hohlraum(Ø700 mm×1 250 mm), the energy of scattered light from a slot hohlraum was 1.3 times that from a hohlraum. With different hohlraum size, the energy of scattered light from a small hohlraum was 1.6 times higher than that from a standard hohlraum(Ø800 mm×1 350 mm). Compared with 1 ns laser, when 2 ns laser interacted with hohlraum, the energy of SRS light was lower because of the decline of laser power, while the duration time was longer. The exper