太赫兹自由电子激光波荡器的设计、测量与优化

闫陇刚; 邓德荣; 张浩; 张伟; 张继东; 杨兴繁; 黎明

doi:10.11884/HPLPB201830.180247

太赫兹自由电子激光波荡器的设计、测量与优化

doi: 10.11884/HPLPB201830.180247

闫陇刚^1,,
邓德荣^1, ,,
张浩¹,
张伟²,
张继东²,
杨兴繁¹,
黎明¹

1.
中国工程物理研究院应用电子学研究所, 四川绵阳 621999
2.
中国科学院上海应用物理研究所, 上海 201800

基金项目:

国家重大科学仪器设备开发专项 2011YQ130018

国家自然科学基金项目 11505174

国家自然科学基金项目 11505173

国家自然科学基金项目 11605190

详细信息

作者简介:
闫陇刚(1986-), 男, 硕士, 从事自由电子激光及其相关技术研究; 441038564@qq.com

通讯作者:
邓德荣(1979-), 男, 学士, 从事自由电子激光及其相关技术研究; lppmcm@163.com

中图分类号: TL503.8
计量
- 文章访问数: 914
- HTML全文浏览量: 202
- PDF下载量: 140
- 被引次数: 0
出版历程
- 收稿日期: 2018-09-26
- 修回日期: 2018-10-17
- 刊出日期: 2018-11-15

Design, measurement and optimization of undulator for terahertz free electron laser

1.
Institute of Applied Electronics, CAEP, Mianyang 621999, China
2.
Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China

摘要

摘要: 波荡器电子轨迹中心偏移和磁场误差对CTFEL装置性能影响很大，通过前期设计和后期测量与优化将其限制在指标要求范围内。在前期设计中尽量避免引入全局性的系统误差：磁结构具有平面反对称结构，保证电子轨迹中心和波荡器磁轴重合；磁结构端部的特殊设计减弱了间隙对出口磁场二次积分的影响；机械系统的大梁和立柱具有良好的刚性，闭环控制系统保证了高的波荡器间隙控制精度，这些措施降低了间隙不一致引入的磁场误差。在后期测量与优化中削弱了磁场的残存全局系统误差和局部随机误差：利用磁场点测台测量了波荡器磁场的纵向和横向分布，通过调节标准单元组件位置对磁场进行了垫补和优化，优化后电子轨迹中心偏移、峰峰值误差、相位误差、好场区及其误差均满足指标要求。
- 太赫兹自由电子激光 /
- 波荡器 /
- 设计 /
- 测量与优化
Abstract: Electron trajectory center deviation and magnetic field errors of undulator have a great influence on the performances of CTFEL facility, which were limited in the range of specification requirements by preliminary design and post measurement and optimization. In the preliminary design, the global system errors were avoided as far as possible: the magnetic structure has a planar anti-symmetric structure to ensure the coincidence of electron trajectory center and undulator magnetic axis; the special design of magnetic structure end weakens the influence of gap on second integral of magnetic field at undulator exit; the beam and frame of the mechanical system have good rigidity and the control system with close-loop configure guarantees high accuracy of the gap control, all of which limit the magnetic field errors caused by the gap inconsistency. The residual global system errors and local random errors of the magnetic field were reduced in the later measurement and optimization: the longitudinal and transverse distributions of magnetic field were measured using magnetic field measurement bench and then the undulator field was shimmed and optimized by adjusting the positions of standard unit components. Finally, the electron trajectory center deviation, peak-to-peak error, phase error and good field range error meet the requirements of specification after optimization.
- terahertz free electron laser /
- undulator /
- design /
- measurement and optimization

HTML全文

图 1 Radia计算模型及计算结果

Figure 1. Radia simulation model and result

下载: 全尺寸图片幻灯片

图 2 出口二次积分随间隙g的变化

Figure 2. Second integral of megnetic field at undulator exit with the gap g

下载: 全尺寸图片幻灯片

图 3 U38机械系统

Figure 3. Mechanical system of U38

下载: 全尺寸图片幻灯片

图 4 大梁和立柱受力变形

Figure 4. Deformations of beam and frame

下载: 全尺寸图片幻灯片

图 5 控制系统组成框图

Figure 5. Block graph of control system

下载: 全尺寸图片幻灯片

图 6 24.0 mm间隙下，磁场纵向分布和垫补优化后的电子轨迹

Figure 6. Longitudinal distribution of magnetic field and trajectory after shimming and optimization under the gap of 24.0 mm

下载: 全尺寸图片幻灯片

图 7 峰峰值误差和相位误差随间隙g的变化

Figure 7. Peak-to-peak error and phase error change with the gap g

下载: 全尺寸图片幻灯片

图 8 峰值磁场随间隙g的变化

Figure 8. Peak field change with the gap g

下载: 全尺寸图片幻灯片

图 9 横向场分布和好场区内误差ε

Figure 9. Transverse distribution of magnetic field and errors ε in good field region

下载: 全尺寸图片幻灯片

表 1 U38波荡器指标要求

Table 1. Specifications of undulator U38

magnetic structure	period /mm	gap /mm	period number	max peak field /T	max undulator parameter K	electron trajectory center deviation/mm	good field range /mm	good field range error /%	peak-to-peak error /%	phase error /(°)	total length /mm
planar, anti-symmetry	38	18~32	42	>0.5	>1.77	< 0.1	>12	< 0.5	< 0.5	< 5	< 1700

下载: 导出CSV

参考文献(19)

[1]	Neil G R, Merminga L. Technical approaches for high-average-power free-electron lasers[J]. Review of Modern Physics, 2002, 74(3): 685-701. doi: 10.1103/RevModPhys.74.685
[2]	Jia Q K. Field integrals error of undulator[J]. Nuclear Instruments & Methods in Physics Research, 1999, 428(2): 589-592.
[3]	Qin B, Tan P, Yang L, et al. Design considerations of a planar undulator applied in a terahertz FEL oscillator[J]. Nuclear Inst and Methods in Physics Research A, 2013, 727(9): 90-96.
[4]	Walker R P. Phase errors and their effect on undulator radiation properties[J]. Physical Review Special Topics-Accelerators and Beams, 2013, 16(1): 122-130.
[5]	Li Y, Faatz B, Pflueger J. Undulator system tolerance analysis for the European X-ray free-electron laser[J]. Review of Modern Physics, 2008, 11(10): 320-325.
[6]	许州, 杨兴繁, 黎明, 等. 高平均功率太赫兹自由电子激光装置设计[J]. 太赫兹科学与电子信息学报, 2013, 11(1): 1-6. https://www.cnki.com.cn/Article/CJFDTOTAL-XXYD201301002.htm Xu Zhou, Yang Xingfan, Li Ming, et al. Design of a high average power terahertz-FEL facility. Journal of Terahertz Science and Electronic Information Technology, 2013, 11(1): 1-6 https://www.cnki.com.cn/Article/CJFDTOTAL-XXYD201301002.htm
[7]	黎明, 杨兴繁, 许州, 等. CAEP太赫兹自由电子激光首次饱和出光[J]. 强激光与粒子束, 2017, 29: 100101. doi: 10.11884/HPLPB201729.170363 Li Ming, Yang Xingfan, Xu Zhou, et al. First lasing of CAEP THz free electron laser. High Power Laser and Particle Beams, 2017, 29: 100101 doi: 10.11884/HPLPB201729.170363
[8]	吴岱, 肖德鑫, 李凯, 等. 砷化镓光阴极直流高压注入器研究进展[J]. 强激光与粒子束, 2015, 27: 045101. doi: 10.11884/HPLPB201527.045101 Wu Dai, Xiao Dexin, Li Kai, et al. Recent progress of GaAs high-voltage DC photo-injector. High Power Laser and Particle Beams, 2015, 27: 045101 doi: 10.11884/HPLPB201527.045101
[9]	王汉斌, 杨兴繁, 潘清, 等. 光阴极直流高压电子枪工程设计[J]. 强激光与粒子束, 2013, 25(s0): 145-148. http://www.hplpb.com.cn/article/id/7812 Wang Hanbin, Yang Xingfan, Pan Qing, et al. Engineering design of photoemission DC high voltage electron gun. High Power Laser and Particle Beams, 2013, 25(s0): 145-148 http://www.hplpb.com.cn/article/id/7812
[10]	Luo X, Lao C, Zhou K, et al. Design and fabrication of the 2×4 -cell superconducting linac module for the free-electron laser[J]. Nuclear Instruments & Methods in Physics Research, 2017, 871: 30-34.
[11]	Vinokurov N. Free electron lasers as a high-power terahertz sources[J]. Journal of Infrared Millimeter & Terahertz Waves, 2011, 32(10): 1123-1143.
[12]	窦玉焕, 束小建, 邓德荣, 等. 中物院高功率THz FEL装置的理论分析和优化设计[J]. 强激光与粒子束, 2013, 25(3): 662-666. doi: 10.3788/HPLPB20132503.0662 Dou Yuhuan, Shu Xiaojian, Deng Derong, et al. Design and simulations of CAEP high power THz FEL. High Power Laser and Particle Beams, 2013, 25(3): 662-666 doi: 10.3788/HPLPB20132503.0662
[13]	Jia Q K. Parameter design considerations for an oscillator IR-FEL[J]. Chinese Physics C, 2017 (1): 187-194.
[14]	Halbach K. Application of permanent magnets in accelerators and electron storage rings[J]. Journal of Applied Physics, 1985, 57(8): 3605-3608. doi: 10.1063/1.335021
[15]	Elleaume P, Onuki A H. Undulators, wigglers and their applications[M]. London: CRC Press, 2002.
[16]	张继东, 周巧根, 张红辉, 等. 可变椭圆极化波荡器EPU10.0的传动控制[J]. 原子能科学技术, 2006, 40(5): 602-604. https://www.cnki.com.cn/Article/CJFDTOTAL-YZJS200605020.htm Zhang Jidong, Zhou Qiaogen, Zhang Honghui et al. Phase driving system for variable elliptically polarized undulator EPU10.0. Atomic Energy Science and Technology, 2006, 40(5): 602-604 https://www.cnki.com.cn/Article/CJFDTOTAL-YZJS200605020.htm
[17]	Tanaka T, Goto S, Hara T, et al. Undulator commissioning by characterization of radiation in X-ray free electron lasers[J]. Review of Modern Physics, 2012, 15(11): 41-73.
[18]	Li P, Wei T, Li Y, et al. Magnetic design of an Apple-X afterburner for the SASE3 undulator of the European XFEL[J]. Nuclear Instruments & Methods in Physics Research, 2017, 870: 103-109.
[19]	Elleaume P, Chavanne J, Faatz B. Design considerations for a 1 Å SASE undulator[J]. Nuclear Instruments & Methods in Physics Research, 2000, 455(3): 503-523.