神光Ⅱ充气黑腔靶受激拉曼散射测量

Measurement of Stimulated Raman Scattering From Gas-filled Hohlraum on Shenguang-Ⅱ Laser Facility

摘要: 激光等离子体不稳定性可能是间接驱动惯性约束聚变（ICF）的一个严重问题。本文基于神光Ⅱ钕玻璃激光装置开展了三倍频激光与充气黑腔靶相互作用实验研究，给出了受激拉曼散射（SRS）反射份额和散射光谱测量结果。由于等离子体尺度的变大，黑腔内电子温度较高，SRS增长率大，背向的SRS散射光能量增加，SRS的反射率由标准黑腔靶的0.05%以下增长到1%～1.5%。

Abstract: The potential for laser-plasma instability is a serious concern for indirect-drive inertial confinement fusion (ICF). In this study, experiments were performed at the Shenguang-Ⅱ laser facility which is Nd: glass laser operated at 351 nm wavelength. The measurements of the total laser scattering losses from stimulated Raman scattering (SRS) in gas-filled hohlraums were presented. It demonstrates that SRS losses increase from under 0.05% to 1%-1.5% due to the inceasement of plasma scale and radiation temperatures.