超快X射线自由电子激光研究进展

贾豪彦; 黄森林; 焦毅; 李京祎; 刘克新; 刘帅; 刘伟航; 刘中琦; 龙天云; 秦伟伦; 赵晟

doi:10.11884/HPLPB202234.220056

超快X射线自由电子激光研究进展

doi: 10.11884/HPLPB202234.220056

贾豪彦^{1, 2,},
黄森林^{1, 2, ,},
焦毅³,
李京祎³,
刘克新^{1, 2},
刘帅^{1, 2},
刘伟航³,
刘中琦^{1, 2},
龙天云^{1, 2, 4},
秦伟伦⁴,
赵晟^{1, 2}

1.
北京大学核物理与核技术国家重点实验室，北京 100871
2.
北京大学物理学院重离子物理研究所，北京 100871
3.
中国科学院高能物理研究所，北京 100049
4.
德国电子同步加速器研究中心，德国汉堡 22603

基金项目: 国家自然科学基金项目(11975039)

详细信息

作者简介:
贾豪彦，jiahaoyan@pku.edu.cn

通讯作者:
黄森林，huangsl@pku.edu.cn

中图分类号: TN248.6
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- 被引次数: 0
出版历程
- 收稿日期: 2022-02-25
- 修回日期: 2022-03-25
- 网络出版日期: 2022-04-15
- 刊出日期: 2022-05-15

Research advances in ultrafast X-ray free-electron lasers

Jia Haoyan^{1, 2
,},
Huang Senlin^{1, 2
, ,},
Jiao Yi³,
Li Jingyi³,
Liu Kexin^{1, 2},
Liu Shuai^{1, 2},
Liu Weihang³,
Liu Zhongqi^{1, 2},
Long Tianyun^{1, 2, 4},
Qin Weilun⁴,
Zhao Sheng^{1, 2}

1.
State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871, China
2.
Institute of Heavy Ion Physics, School of Physics, Peking University, Beijing 100871, China
3.
Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China
4.
Deutsches Elektronen-Synchrotron (DESY), Hamburg 22603, Germany

摘要

摘要:
现代光源的发展不断推动着人们从更深层次上理解物质的基本结构和动力学行为。X射线自由电子激光作为最先进的光源，其超高的峰值功率、超短的脉冲长度和优良的相干性，为人们以原子级时空分辨率探测和操控物质中的超快过程提供了可能。目前全世界已有多个X射线自由电子激光装置建成并投入使用，在原子分子物理、化学、生命科学、材料科学等各学科应用中都显示出了重要价值。同时大量的研究工作也集中于继续提高X射线自由电子激光的性能，包括把脉冲持续时间从fs量级进一步缩短至as量级，这将为超快科学的发展带来新突破。以超快脉冲产生为主线，综述了近年来超快X射线自由电子激光产生方案的研究进展，从产生原理、方案特性、最新成果等方面介绍了各类产生方案，总结对比了各方案的优缺点，最后对超快X射线自由电子激光的未来发展方向进行了展望。
- X射线 /
- 自由电子激光 /
- 超快光学 /
- 阿秒脉冲
Abstract:
Advances in modern light sources continue to improve our understanding of the fundamental structure and microscopic dynamics of matter. As the most advanced light source, X-ray free-electron lasers provide the brightest X-rays with ultrahigh peak power, ultrashort pulse length, and excellent coherence, making it possible to detect and manipulate ultrafast processes in atomic and molecular systems. X-ray free-electron laser facilities in operation worldwide have shown great value in the application fields of physics, chemistry, biology, material science, etc. Furthermore, many efforts have focused on improving the performance of X-ray free-electron lasers, including reducing the pulse duration from femtosecond to attosecond for opening new frontiers in ultrafast science. This paper mainly reviews the recent progress of ultrafast X-ray free-electron lasers and summarizes various schemes in terms of their generation mechanisms, unique properties and latest results. Finally, it predicts the future development of ultrafast X-ray free-electron lasers.
- X-ray /
- free-electron laser /
- ultrafast optics /
- attosecond pulse

HTML全文

图 1 自由电子激光工作原理

Figure 1. Working principle of a free-electron laser

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图 2 能量调制方案示意图

Figure 2. Schematic diagram of energy modulation scheme

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图 3 电流调制方案示意图

Figure 3. Schematic diagram of current modulation scheme

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图 4 LCLS ESASE实验装置示意图^[47]

Figure 4. Schematic illustration of the ESASE experiment at LCLS^[47]

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图 5 开槽箔片方案示意图

Figure 5. Schematic diagram of slotted foil scheme

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图 6 基于去啁啾器横向尾场的新鲜束技术^[68]

Figure 6. Fresh-slice technique based on the transverse wakefields of a dechirper^[68]

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图 7 LCLS非线性束团压缩实验示意图^[78]

Figure 7. Schematic illustration of nonlinear bunch compression at LCLS^[78]

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图 8 Thompson等人提出的锁模FEL方案示意图^[80]

Figure 8. Schematic diagram of the mode-locked FEL scheme proposed by Thompson et al.^[80]

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图 9 Dunning等人提出的锁模FEL方案示意图^[81]

Figure 9. Schematic diagram of the mode-locked FEL scheme proposed by Dunning et al.^[81]

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图 10 阿秒软X射线级联放大方案示意图^[87]

Figure 10. Schematic diagram of attosecond soft X-ray cascade amplification scheme^[87]

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图 11 啁啾微聚束方案示意图^[88]

Figure 11. Schematic diagram of chirped microbunching scheme^[88]

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图 12 各类超快XFEL脉冲产生方案比较：图中蓝色标记表示产生硬X射线的方案，品红色标记表示产生软X射线的方案，带有橙色实心点标记的表示已经在FEL装置上成功验证的实验结果，蓝色阴影区域为当前装置能够达到的脉冲宽度和峰值功率范围

Figure 12. Comparison of various ultrafast XFEL pulse generation schemes. The blue markers represent hard X-ray generation schemes and magenta markers represent soft X-ray generation schemes. The orange filled markers indicate the schemes have been validated on FEL facilities. The shaded blue area indicates the parameter space that can be achieved currently

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表 1 图12中各数据点所代表方案的主要参数值

Table 1. Main parameters of the schemes presented in Fig.12

scheme	pulse duration (FWHM)/as	pulse peak power/GW	wavelength/photon energy	reference
energy modulation	100	0.005	1 nm	[29]
	300	1	0.1 nm	[28]
	300	100	0.15 nm	[30]
	200	100	0.15 nm	[31]
	400	100	900 eV/ 1100 eV	[40]
	400	1 000	1.22 nm/ 2.48 nm	[33]
current modulation	250	40	0.15 nm	[42]
	100	2.3	0.15 nm	[43]
	146	58	0.1 nm	[45]
	210	25	0.15 nm	[46]
	280	100	905 eV	[47]
	250	120	940 eV	[50]
	1 000	39	560 eV	[51]
emittance spoiling	2 000	10	8 keV	[52]
	3 800	2.5	1.1 nm	[55]
	420	30	5.6 keV	[56]
	10 000	30	1.5 keV	[59]
orbit control	29 000	12	0.15 nm	[60]
	115	100	0.15 nm	[61]
	5 000	140	670 eV	[68]
low charge bunch compression	300	10	0.15 nm	[72]
	2 000	20	1.5 nm	[73]
	2 600	10	1 keV	[74]
	140	35	0.15 nm	[77]
	200	50	5.6 keV	[78]
	326	4.3	7.36 keV	[79]
mode-locked FEL	23	6	0.15 nm	[80]
mode-locked FEL	1.5	1.5	0.1 nm	[81]
cascade amplification	228	1 000	0.1 nm	[82]
	500	1 000	0.1 nm	[83]
	53	6 600	10 keV	[84]
	100	300	0.1 nm	[85]
	80	1 700	0.15 nm	[86]
	260	550	1.5 nm	[87]
chirped microbunching	46	1.2	8.6 nm	[88]

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表 2 各类超快XFEL脉冲产生方案特性汇总

Table 2. A summary of various ultrafast XFEL pulse generation schemes

scheme		spectral range	isolated pulse/ pulse train	synchronization to optical laser	high repetition frequency (MHz)	hardware requirements and feasibility
energy modulation		all (soft X-ray to hard X-ray)	isolated/train	yes	no (self-modulation method-yes)	high power external laser, need to add modulators
current modulation		all	isolated/train	yes	no (self-modulation method-yes)	high power external laser, need to add modulators
emittance spoiling	slotted foil	all	isolated	no	no	non-invasive hardware, can be used at any facilities
emittance spoiling	optical shaping	all	isolated	yes	yes	no additional hardware, can be used at any facilities
orbit control	RF deflector	all	isolated	no	yes	no additional hardware, can be used at any facilities
	laser modulation			yes	no	high power external laser, need to add modulators
	transverse wakefield			no	yes	add dechirper before the undulator
	dispersion based			no	yes	no additional hardware, can be used at any facilities
low charge bunch compression		all	isolated	no	yes	no additional hardware, can be used at any facilities
cascade amplification (based on slotted foil, orbit control, ESASE, the specific attributes are the same as above)		all	isolated/train	——	——	add chicane between undulators, need a dedicated line
mode-locked FEL		all	train	yes	no	high power external laser and chicanes, need a dedicated line
chirped microbunching		soft X-ray	isolated	yes	——	seed laser and modulators，need a dedicated line

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