强流目标的DC-SRF-II光阴极驱动激光系统设计  

Design of the photocathode drive laser system for high current electron beam operation of DC-SRF-II gun

作　　者：吴桐 徐航 徐金强[3] 李京祎 黄森林 Wu Tong;Xu Hang;Xu Jinqiang;Li Jingyi;Huang Senlin(State Key Laboratory of Nuclear Physics and Technology,Peking University,Beijing 100871,China;Institute of Heavy Ion Physics,School of Physics,Peking University,Beijing 100871,China;Key Laboratory of Particle Acceleration Physics&Technology,Institute of HighEnergy Physics,Chinese Academy of Sciences,Beijing 100049,China;Spallation Neutron Source Science Center,Dongguan 523803,China)

机构地区：[1]北京大学核物理与核技术国家重点实验室,北京100871 [2]北京大学物理学院重离子物理研究所,北京100871 [3]中国科学院高能物理研究所粒子加速物理与技术重点实验室,北京100049 [4]散裂中子源科学中心,广东东莞523803

出　　处：《强激光与粒子束》2022年第10期156-162,共7页High Power Laser and Particle Beams

基　　金：北京大学核物理与核技术国家重点实验室自主科研课题(NPT2022ZZ01);北京大学核物理与核技术国家重点实验室开放课题(NPT2020KFY15)。

摘　　要：为推动北京大学超导加速器实验装置不断向强流目标迈进,提出100 W红外高重频光阴极驱动激光的设计方案,主放大器采用先进的光子晶体增益光纤,保证输出光束的质量。对激光系统中的关键问题,如各部分功率指标、脉冲展宽和压缩、激光耦合等进行了设计,并且考虑了激光的非线性影响。为实现强流加速器开机运行所必备的诊断模式,也提出了对于高重频激光进行两级选频的独特设计方案。将高速的SOA光开关和低速的声光调制器相结合,产生宏脉冲结构的输出激光,从而实现加速器在诊断模式下的运行。We present the design of a 100 W high repetition rate photocathode drive laser system for realizing high average current operation of the superconducting accelerator at Peking University. To achieve good beam quality and reliability, we choose photonic crystal fiber(PCF) as the gain medium of the main amplification unit. In addition,we address several key issues for the drive laser system, including the evaluation of the output power of each amplification unit, the design of pulse stretcher and compressor, the optimization of free space coupling setups for pump pulse and seed pulse, etc. We also combine a high-speed semi-conductor optical amplifier(SOA) optical switch with a low-speed acousto-optic modulator(AOM) to achieve the necessary diagnostic mode for the intense electron beam accelerator. This unique design is of importance for the photocathode drive laser with the repetition rate around or above 100 MHz.

关 键 词：强流电子加速器 光阴极驱动激光 宏脉冲诊断模式 激光传输 

分 类 号：TN248[电子电信—物理电子学]