FEL驱动激光器的研究

为了获得高亮度和高品质的电子束,在自由电子激光实验装置中采用光阴极注入器作为电子源,其驱动激光器系统采用主振功率放大结构,振荡器为二极管抽运连续锁模激光器,放大器为一级双程及两级单程二极管脉冲抽运放大,后接4倍频系统.经过工程研制及调试,获得的输出指标为:波长266nm,微脉冲能量4μJ,宏脉冲宽度2μs至6μs可调,微脉冲能量抖动优于3%.结果表明,采用Cs2Te阴极的光阴极注入器实验,该系统能够获得不低于40A的电子束流,达到了自由电子激光实验对电子源的束流要求.

Research of the drive laser for FEL

In order to achieve high quality and high brightness electron beam,a photocathode injector is used as the electron source in the experimental setup of a free electron laser (FEL).The drive laser system is a master oscillator power amplifier configuration,consisting of a confinuous wave diode-pumped mode-locked oscillator,one double-pass and two single-pass regenerative diode-pumped pulse amplifiers and a four fold frequency conversion part.After adjustment,single micropulse energy of 4μJ with less than 3 percent of jitter at wavelength 266nm was obtained.These micropulses were contained within a macropulse envelope as long as 2μs to 6μs.In the experiments,adopting C2Te photocathode as the photoinjector,more than 40A electron beam was obtained,meeting the requirement of beam current for the FEL.