论文部分内容阅读
主要介绍自由电子激光相干强太赫兹源(FEL-THz)装置上的砷化镓光阴极直流高压注入器的研究进展,并讨论其驱动未来高重复频率短波长自由电子激光器的差距。通过综合砷化镓阴极寿命的三大影响因素,提出了其工作寿命的定性物理模型;通过该模型对阴极和注入器进行优化,在直流高压电子枪上得到了5mA,32min的连续稳定输出;测量了电子束在4.8mA下归一化发射度约为4.0πmm·mrad,阴极热发射度约为0.6πmm·mrad,电子束本征横向能量约为92meV,250keV电子束在距离阴极90.6cm处纵向均方根长度约为11.5ps。这一束流状态已经基本满足FEL-THz需求。
This paper mainly introduces the research progress of gallium arsenide (GaAs) cathode DC high voltage implanter on free-electron laser-induced terahertz source (FEL-THz) and discusses the gap between the new high frequency repetition rate and short wavelength free electron lasers. Through the comprehensive analysis of the three factors affecting the lifetime of gallium arsenide cathode, a qualitative and physical model of its working life was proposed. Through the optimization of the cathode and injector, a continuous and stable output of 5mA and 32min was obtained on the DC high voltage electron gun. The electron beam has a normalized emissivity at 4.8 mA of about 4.0πmm · mrad, a cathode thermal emissivity of about 0.6πmm · mrad, an electron beam intrinsic transverse energy of about 92meV, a 250 keV electron beam at a distance of 90.6cm from the cathode The root mean square length is about 11.5ps. This beam state has basically met the FEL-THz requirements.