高平均功率高亮度ERL光源上使用的光阴极驱动激光振荡源实验研究

The forth generation light source based on ERL features high brightness and high average power, and one of its key components is a photocathode with very small emittance and high average current. The photocathode drive laser determines the quality of the electron bunches. International counterparts at Jlab, Cornel University and KEK in the research process have found that the laser oscillators they bought have problems. This application proposes an innovative approach to construct a high repetition rate laser oscillator by using fiber optic couplers. The laser pulses will naturally interpolates while passing through these passive components with delay lines to construct a high repetition rate pulses which repetition rate can be changed easily. The experimental study will solve the stability problem of laser oscillator. Moreover the difficulty of ramping up beam current while the ERL facility turned on can be overcome by gradually changing the repetition rate of our laser oscillator. In the future, the innovative ideas can be used to build a drive laser system with stable and reliable performance suitable for high-brightness high average power ERL machine which power ramping up easily. In the future, the innovative ideas can be used to build a drive laser system with stable and reliable performance suitable for high-brightness high average power ERL machine which power ramping up easily. So the application is of great significance for the construction of an ERL facility in the future.

基于ERL技术的第四代光源的显著特征是高平均功率和高亮度，其中关键技术之一是小发射度高平均流强的光阴极。光阴极驱动激光决定着光阴极电子束团的质量，稳定的高重复频率激光振荡源非常重要。国际上Jlab实验室，Cornel大学和日本KEK的研究同行在进行光阴极技术的研究过程中，都发现现有的光阴极驱动激光的振荡源存在问题，不能稳定工作。本项目提出一种创新方法，用光纤定向耦合器构成无源器件，实现低重复频率激光脉冲自然内插，构造出高重复频率的激光振荡源。这样构造的振荡源也容易改变重复频率。通过对该方法实验研究，可以解决目前的稳定性的问题。同样重要的是ERL装置运行时，需要逐步提升功率的难题也得以解决。这为未来建立一套非常适合高亮度高平均功率ERL应用的光阴极驱动激光系统提供了创新思路，对未来的ERL加速器光源装置建设具有重要的意义。

基于ERL技术的第四代光源的显著特征是高平均功率和高亮度，其中关键技术之一是小发射度高平均流强的光阴极。光阴极驱动激光决定着光阴极电子束团的质量，稳定的高重复频率激光振荡源非常重要。国际上Jlab实验室，Cornel大学和日本KEK的研究同行在进行光阴极技术的研究过程中，都发现现有的光阴极驱动激光的振荡源存在问题，不能稳定工作。本项目提出一种创新方法，用光纤定向耦合器构成无源器件，实现低重复频率激光脉冲自然内插，构造出高重复频率的激光振荡源。这样构造的振荡源也容易改变重复频率。通过对该方法实验研究，可以解决目前的稳定性的问题。同样重要的是ERL装置运行时，需要逐步提升功率的难题也得以解决。这为未来建立一套非常适合高亮度高平均功率ERL应用的光阴极驱动激光系统提供了创新思路，对未来的ERL加速器光源装置建设具有重要的意义。在该项目研究中，创新提出了脉冲内插延迟环节的高精度标定方法，经过检验，能够达到亚皮秒的使用要求。