Free-electron lasers in China today and tomorrow

Abstract

In this paper the free-electron laser (FEL) study in China is presented. The FEL theoretical research in China commenced in the mid- 1970s, but experiments commenced later. In 1987 Hefei National Synchrotron Radiation Laboratory, in cooperation with Shanghai Institute of Optics and Fine Mechanics, produced an experiment based on rf linac of 30 MeV, in which an infrared radiation at wavelength of 10 µm is observed. In 1988 China Academy of Engineering Physics (CAEP) had performed an experiment based on pulse line accelerator, in which 7.6 MW radiation has been observed at 36.9 GHz representing 5% efficiency. These early experiments were characterized by small efficiency due to poor quality of electron beams at the time. However, now the induction linac of 4 MeV and 1 kA with qualitative electron beam is projected for SG 1 FEL amplifier by CAEP and 30 MeV rf linac is being upgraded by Institute of High Energy Physics to provide electron beam for FEL oscillator in the infrared region. The FEL with electromagnet wave pump is projected by University of Electronics Science and Technology of China. The superconductor accelerator is by accelerator laboratory of Peking University and the Cherenkov FEL experiment is produced by Changsha Polytechnic Institute. Now the FEL research is intensely produced by theoretical and experimental aspect in China.