强激光与粒子束, 2014, 26 (3): 034005, 网络出版: 2014-03-31
行波前置短磁聚焦飞秒条纹管设计
Design of magnetic focusing femtosecond streak tube with prepositive traveling wave deflector
飞秒条纹管 短磁聚焦透镜 行波偏转板 时间分辨力 空间分辨力 femtosecond streak tube short focusing length magnetic lens traveling wave deflector time resolution spatial resolution
摘要
设计了一款长度为265 mm的飞秒条纹管。采用短磁聚焦透镜和行波偏转板,并将行波偏转板置于磁透镜之前以提高偏转灵敏度。采用蒙特卡罗方法对阴极表面理想点和阴极狭缝发射的光电子初始参量进行了模拟抽样,用CST软件的Particle Tracking模块模拟跟踪了光电子的运行轨迹,统计分析了光电子在最佳像面上的位置分布和渡越时间,给出了光电子在最佳像面上的点扩展函数和调制传递函数。计算结果显示,所设计的条纹管阴极有效尺寸达到6 mm,放大率为2.4~2.5,动态空间分辨力大于55 lp/mm。经保守估算,条纹管的时间分辨力有望达到245 fs。
Abstract
A 265 mm long magnetic focusing femtosecond streak tube with a prepositive traveling wave deflector was theoretically designed. The initial parameters of the electrons emitted both from an ideal point and a slit on the surface of the photoelectric cathode were sampled with Monte Carlo method. The trajectory of the electrons were followed in the CST particle studio, after which the distribution of the electrons on the best image plane and the transit time of the electrons were statistically analyzed. To evaluate the characteristics of the streak tube, this paper also calculated the modulation transform function. The results show that the diameter of the effective area on the photoelectric cathode reaches up to 6 mm, while the amplification rate turns to be 2.4~2.5. By conservative estimates, the time resolution is expected to reach 245 fs.
王强强, 田进寿, 丁永坤, 温文龙, 刘蓉, 卢裕, 徐向晏, 曹希斌, 王兴, 王俊锋. 行波前置短磁聚焦飞秒条纹管设计[J]. 强激光与粒子束, 2014, 26(3): 034005. Wang Qiangqiang, Tian Jinshou, Ding Yongkun, Wen Wenlong, Liu Rong, Lu Yu, Xu Xiangyan, Cao Xibin, Wang Xing, Wang Junfeng. Design of magnetic focusing femtosecond streak tube with prepositive traveling wave deflector[J]. High Power Laser and Particle Beams, 2014, 26(3): 034005.