纳秒级激光惯性约束装置靶室内电磁脉冲数值模拟  

Numerical Simulation of Electromagnetic Pulse in Target Chamber of Nanosecond Laser Inertial Confinement Facility

作　　者：卢志永 徐志谦 孟萃[1,2] 金晗冰 Lu Zhiyong;Xu Zhiqian;Meng Cui;Jin Hanbing(Department of Engineering Physics,Tsinghua University,Beijing 100084,China;Key Laboratory of Particle&Radiation Imaging(Tsinghua University),Ministry of Education,Beijing 100084,China;Beijing Jinghang Computing and Communication Research Institute,Beijing 100074,China)

机构地区：[1]清华大学工程物理系,北京100084 [2]清华大学粒子技术与辐射成像教育部重点实验室,北京100084 [3]北京京航计算通讯研究所,北京100074

出　　处：《光学学报》2020年第9期73-79,共7页Acta Optica Sinica

摘　　要：为了探索纳秒级激光惯性约束装置靶室内电磁脉冲(EMP)的物理规律,实验室利用自主研发的EMPIC-2D计算软件开展数值模拟研究。软件将激光与靶作用后产生的逃逸电子作为输入参数,将电磁脉冲强度随时间的变化作为输出。模拟结果发现,纳秒级激光打靶产生的逃逸电子激发的EMP的频率主要分布在0 MHz^2 GHz之间,随着出射波形宽度的变宽,纳秒级激光产生的EMP的高频信号成分减少,而低频成分变化较小;在靠近靶的位置,随着出射时间的延长(1~10 ns),电磁场峰值逐渐降低;与皮秒级激光的模拟结果比较发现,纳秒级激光产生的电磁场的强度较小,低频成分与皮秒级相似,而大于1 GHz的高频成分大量减少。To study electromagnetic pulse(EMP)in the target chamber of nanosecond laser inertial confinement facility,this study uses the independently developed EMPIC-2Dcalculation software to perform the numerical simulation.The escaping electrons generated by the interaction of high-intensity laser pulses with solid target were considered as the input parameter and the electromagnetic pulse intensity in the chamber were considered as the as output.Results show that EMP frequency mostly distributes between 0 MHz and 2GHz.As the width of the ejection waveform widens,the high-frequency nanosecond signal component decreases,while the low-frequency component slightly changes.Peak values of electromagnetic field(close to the electron emission point)also decrease with the extension of ejection time(1--10ns).Compared with the simulation results of picosecond laser pulses,nanosecond simulation results have lower electromagnetic intensity.Its low frequency compositions are similar to picosecond results;however,high frequency compositions higher than 1GHz are observed to greatly decrease.

关 键 词：激光光学 激光惯性约束装置 电磁脉冲 逃逸电子 数值模拟 

分 类 号：TN202[电子电信—物理电子学] O441.4[理学—电磁学]