激光等离子体不稳定性及其抑制方案研究  

Laser plasma instabilities and their suppression strategies

作　　者：余诗瀚 李晓锋 翁苏明[1,2] 赵耀 马行行[1,2] 陈民 盛政明 Yü Shihan;Li Xiaofeng;Weng Suming;Zhao Yao;Ma Hanghang;Chen Min;Sheng Zhengming(School of Physics and Astronomy,Shanghai Jiaotong University,Shanghai 200240,China;Collaborative Innovation Center of IFSA,Shanghai Jiaotong University,Shanghai 200240,China;Key Laboratory of High Power Laser and Physics,Shanghai Institute of Optics and Fine Mechanics,Chinese Academy of Sciences,Shanghai 201800,China)

机构地区：[1]上海交通大学物理与天文学院激光等离子体实验室,上海200240 [2]上海交通大学IFSA协同创新中心,上海200240 [3]中国科学院上海光学精密机械研究所高功率激光物理联合实验室,上海201800

出　　处：《强激光与粒子束》2021年第1期108-124,共17页High Power Laser and Particle Beams

基　　金：国家重大专项项目;国家自然科学基金项目(11775144,11975154)。

摘　　要：受激拉曼散射、受激布里渊散射等激光等离子体不稳定性(LPI)是激光等离子体物理领域最重要的研究课题之一。特别是在激光驱动的惯性约束聚变中,LPI会造成相当份额的激光能量损失,破坏辐射对称性,产生的超热电子还会预热靶丸,进而影响压缩效率和聚变能量增益。近期,在美国国家点火装置上开展的实验表明对LPI物理过程的充分理解和有效控制对成功实现ICF点火至关重要。我们对近期LPI方面的一系列研究进展进行了简单介绍与讨论。首先,回顾了描述LPI过程的三波耦合理论,由此得出了LPI在线性阶段的增长率。接着讨论了一些复杂情景下的LPI物理过程,譬如LPI的非线性发展阶段、级联LPI、多光束LPI以及LPI间的非线性耦合。最后,着重介绍了一系列抑制LPI的技术方案,包括束匀滑技术、光束时域整形、宽带激光、偏振旋转激光以及外加磁场等。The issue of laser plasma instabilities(LPIs)including stimulated Raman scattering,stimulated Brillouin scattering and so on is one of the most fascinating subjects in laser plasma physics.In particular,LPIs may cause significant laser energy loss and produce hot electrons to preheat fusion targets,which affect target compression and fusion energy gain in laser-driven inertial confinement fusion.Recent experiments carried out on the National Ignition Facility,the largest laser facility in the world for laser fusion,indicate that the understanding and the control of LPIs are essential to the realization of laser fusion.In this paper,we present a review on recent studies of LPIs.Firstly,we retrospect the classical theoretical model of LPIs,which offers a good estimation of growth rate in the linear development stage.Then,we discuss some progresses on the understanding of LPIs in more complex and real scenarios,such as LPI development in the nonlinear regions,cascaded LPIs,multi-beam LPIs,and nonlinear couplings between LPIs.Following the exploration of LPI physics,we emphasize on the strategies for the control of LPIs,including beam smoothing techniques,temporal profile shaping,broadband laser,laser polarization rotation,external magnetic field and so on.

关 键 词：激光等离子体不稳定性 惯性约束聚变 受激拉曼散射 受激布里渊散射 宽带激光 

分 类 号：O534[理学—等离子体物理]