A two-stage echo-enabled harmonic generation(EEHG)scheme is proposed for a superconducting linacdriven FEL to produce coherent hard X-rays.Electron beams of quite different bunch lengths are separately used in each st...A two-stage echo-enabled harmonic generation(EEHG)scheme is proposed for a superconducting linacdriven FEL to produce coherent hard X-rays.Electron beams of quite different bunch lengths are separately used in each stage of EEHG,and a monochromator is designed to purify the radiation from the first stage for seeding the second stage.Theoretical analysis and 3D simulations indicate that the proposed scheme can generate high-repetition-rate coherent hard X-ray pulses directly from a conventional UV seed laser.展开更多
We investigate storage ring-based Echo-Enabled Harmonic Generation（EEHG） superradiant undulator radiation as a possible scheme to obtain shorter wavelengths at the HLS-Ⅱ（Hefei Light Source-Ⅱ） storage ring. In th...We investigate storage ring-based Echo-Enabled Harmonic Generation（EEHG） superradiant undulator radiation as a possible scheme to obtain shorter wavelengths at the HLS-Ⅱ（Hefei Light Source-Ⅱ） storage ring. In this paper we give the designation of the storage ring based EEHG up to the 26 th harmonic, where 31 nm vacuum ultraviolet light is radiated from an 800 nm seeded laser. The novelty of our design is that both the two dispersion sections of EEHG are realized by the storage ring＇s own magnet structure. In particular, the whole ring is used as the first dispersion section, and two modulators of the traditional EEHG can be done with the same undulator. These two dispersion sections are realized by changing the superperiod of the present lattice structure, and more precisely by changing the focusing strengths of the present structure. Since no additional magnets and chicanes are used,the beam circulates around the storage ring repeatedly, and thus this storage ring-based EEHG can have a higher repetition rate than a linac-based EEHG.展开更多
Using the recently proposed echo-enabled harmonic generation （EEHG） free-electron laser （FEL） scheme, it is shown that operating the Shanghai deep ultraviolet FEL （SDUV-FEL） with single-stage to higher harmonics...Using the recently proposed echo-enabled harmonic generation （EEHG） free-electron laser （FEL） scheme, it is shown that operating the Shanghai deep ultraviolet FEL （SDUV-FEL） with single-stage to higher harmonics is very promising, with higher frequency up-conversion effciency, higher harmonic selectivity and lower power requirement of the seed laser. The considerations on a proof-of-principle experiment and expected performance in SDUV-FEL are given.展开更多
基金partially supported by the National Development and Reform Commission([2013]2347)National Natural Science Foundation of China(No.11475250)the Youth Innovation Promotion Association CAS(2015209)
文摘A two-stage echo-enabled harmonic generation(EEHG)scheme is proposed for a superconducting linacdriven FEL to produce coherent hard X-rays.Electron beams of quite different bunch lengths are separately used in each stage of EEHG,and a monochromator is designed to purify the radiation from the first stage for seeding the second stage.Theoretical analysis and 3D simulations indicate that the proposed scheme can generate high-repetition-rate coherent hard X-ray pulses directly from a conventional UV seed laser.
基金Supported by National Natural Science Foundation of China(11305170)
文摘We investigate storage ring-based Echo-Enabled Harmonic Generation（EEHG） superradiant undulator radiation as a possible scheme to obtain shorter wavelengths at the HLS-Ⅱ（Hefei Light Source-Ⅱ） storage ring. In this paper we give the designation of the storage ring based EEHG up to the 26 th harmonic, where 31 nm vacuum ultraviolet light is radiated from an 800 nm seeded laser. The novelty of our design is that both the two dispersion sections of EEHG are realized by the storage ring＇s own magnet structure. In particular, the whole ring is used as the first dispersion section, and two modulators of the traditional EEHG can be done with the same undulator. These two dispersion sections are realized by changing the superperiod of the present lattice structure, and more precisely by changing the focusing strengths of the present structure. Since no additional magnets and chicanes are used,the beam circulates around the storage ring repeatedly, and thus this storage ring-based EEHG can have a higher repetition rate than a linac-based EEHG.
基金supported by the National Development and Reform Commission([2013]2347)National Natural Science Foundation of China(11475250)the Shanghai Natural Science Foundation(13ZR1464700)
基金This work was partially supported by the National Development and Reform Commission （[201312347）, the National Natural Science Foundation of China （11475250, 11175240, 11275253 and 11322550） and the National Basic Research Program of China （2015CB859700）.
文摘使回响能的泛音产生(EEHG ) 计划为高效地在起始的种子激光的很高的泛音产生强烈协调放射保持有希望的前景。在这份报纸，我们学习与单个阶段 EEHG 安装操作上海 X 光检查免费电子的激光测试设备的可行性。与存在数字代码的联合，就各种各样的三维的效果而言的 start-to-end 模拟被执行了显示出 EEHG FEL 的可能的表演。模拟结果证明阶段 EEHG 能高产生的一个单身者从紫外种子激光直接与狭窄的带宽驱动软 X 光检查放射脉搏。在放射激光的泛音的帮助下技术或升级的线性加速器，我们也显示出与单个阶段 EEHG 在水窗户中产生协调软 X 光检查放射的可能性。
基金Supported by Major State Basic Research Development Program of China (2002CB713600)
文摘Using the recently proposed echo-enabled harmonic generation （EEHG） free-electron laser （FEL） scheme, it is shown that operating the Shanghai deep ultraviolet FEL （SDUV-FEL） with single-stage to higher harmonics is very promising, with higher frequency up-conversion effciency, higher harmonic selectivity and lower power requirement of the seed laser. The considerations on a proof-of-principle experiment and expected performance in SDUV-FEL are given.
