汤姆逊硬X射线源中锁模脉冲激光稳频方法

Frequency stabilization of mode-locked laser for Thomson scattering X-ray source

汤姆逊硬X射线源中,光阴极微波电子枪要求触发激光脉冲与腔中微波场相位的精确时间同步。理论分析了锁模脉冲激光器相位噪声,探讨了对激光脉冲相位探测和控制的方法,并通过实验构建了激光相位抖动测量系统和锁相环稳频回路,用基频鉴相信号驱动压电陶瓷晶体改变谐振腔长,实现了从开环3.42ps到闭环1.46 ps的均方根相位抖动的测量和控制。

The photocathode RF gun requests accurate synchronization between laser pulse and RF phase in Thomson scattering X-ray source facility. Based on theoretical analysis on mode-locked laser phase noise, methods of phase error detection and feedback control technique are discussed. An experimental system has been established including phase jitter measurement and PLL feedback control, which changes laser optical length using a PZT. The RMS laser phase jitter has reached 3.42 ps at open loop, and 1.46 ps at close loop.