Recent Experimental Results of Coherent THz Sources Driven by Nsrrc High Brightness Photo-injector
Ming-Chang Chou1*, An-Ping Lee1, Nuan-Ya Huang1, Jiing-Yi Hwang1, Cheng-Chih Liang1, Hwang, Ching-Shiang1, Gwo-Huei Luo1, Kuo-Tung Hsu1, Wai-Keung Lau1
1National Synchrotron Radiation Research Center, Hsinchu, Taiwan
* Presenter:Ming-Chang Chou,
Generation and characterization of coherent THz sources based on coherent undulator radiation (CUR) and coherent transition radiation (CTR) driven by the high brightness photo-injector system is achieved at NSRRC. The photo-injector system consists of a laser-driven photocathode rf gun and one 5.2-m long S-band accelerating linac. Electron bunches in the linac can be accelerated and compressed simultaneously by velocity bunching. Narrow-band tunable fully-coherent THz radiation can be produced from a U100 planar undulator when it is driven by a 100 pC electron bunch with compressed bunch length of ~ 100 fs and energy of ~ 30 MeV. In addition, broadband THz sources from CTR can be generated when the ultrashort electron beam passes through a metal foil and used to determine the bunch length by autocorrelation technique. The experimental setup and the measurement of the power and the frequency spectrum of the THz CUR and the ultrashort electron bunch length derived from the THz CTR are reported.

Keywords: photo-injector, coherent undulator radiation, coherent transition radiation, THz