Coherent light with orbital angular momentum(OAM)is of great interest.Recently,OAM light generation by coupling a relativistic electron beam with a Gaussian mode laser pulse at the high harmonics of a helical undulato...Coherent light with orbital angular momentum(OAM)is of great interest.Recently,OAM light generation by coupling a relativistic electron beam with a Gaussian mode laser pulse at the high harmonics of a helical undulator has been demonstrated experimentally.In this paper,the possibility of delivering coherent OAM light at the 3^(rd)harmonic of the Gaussian mode seed laser is discussed for the Shanghai deep ultraviolet freeelectron laser(SDUV-FEL).Considerations are given on the experiment setup,the expected performance and the possible measurement method.展开更多
Using proper beam energy chirp and the undulator detuning effect,we propose a modified optical replica synthesizer scheme to characterize the temporal structure of a relativistic electron bunch,which predicts a 100-fs...Using proper beam energy chirp and the undulator detuning effect,we propose a modified optical replica synthesizer scheme to characterize the temporal structure of a relativistic electron bunch,which predicts a 100-fs temporal resolution in numerical simulation.The proof of principle experiment demonstrates a peak current of 9 A and a slice energy spread of about 0.5 keV for the uncompressed electron beam of the Shanghai Deep UV Free Electron Laser Facility.展开更多
基金Supported by the Major State Basic Research Development Program of China(2011CB808300)the National Natural Science Foundation of China(11175240,11205234 and 11322550)
文摘Coherent light with orbital angular momentum(OAM)is of great interest.Recently,OAM light generation by coupling a relativistic electron beam with a Gaussian mode laser pulse at the high harmonics of a helical undulator has been demonstrated experimentally.In this paper,the possibility of delivering coherent OAM light at the 3^(rd)harmonic of the Gaussian mode seed laser is discussed for the Shanghai deep ultraviolet freeelectron laser(SDUV-FEL).Considerations are given on the experiment setup,the expected performance and the possible measurement method.
基金Supported by the National Natural Science Foundation of China under Grant No 11175240the Shanghai Natural Science Foundation under Grant No 09JC1416900.
文摘Using proper beam energy chirp and the undulator detuning effect,we propose a modified optical replica synthesizer scheme to characterize the temporal structure of a relativistic electron bunch,which predicts a 100-fs temporal resolution in numerical simulation.The proof of principle experiment demonstrates a peak current of 9 A and a slice energy spread of about 0.5 keV for the uncompressed electron beam of the Shanghai Deep UV Free Electron Laser Facility.