Li H, Chen L-J, Cheng H P H, May J E, Smith S, Muehlig K, Uttamadoss A, Frisch J C, Fry A R, Kärtner F X, Bucksbaum P H
Opt Lett. 2014 Sep 15;39(18):5325-8. doi: 10.1364/OL.39.005325.
Using balanced detection in both the radio frequency (RF) and the optical domain, we remotely synchronize the repetition rate of a Ti:sapphire oscillator to an Er-doped fiber oscillator through a 360 m length-stabilized dispersion compensated fiber link. The drift between these two optical oscillators is 3.3 fs root mean square (rms) over 24 hours. The 68 MHz Er-doped fiber oscillator is locked to a 476 MHz local RF reference clock, and serves as a master clock to distribute 10 fs-level timing signals through stabilized fiber links. This steady remote two-color optical-to-optical synchronization is an important step toward an integrated femtosecond fiber timing distribution system for free-electron lasers (FELs); it does not require x-ray pulses, and it makes sub-10-fs optical/x-ray pump-probe experiments feasible.
通过在射频（RF）和光域中使用平衡检测，我们通过一条360米长的长度稳定的色散补偿光纤链路，将钛宝石振荡器的重复频率远程同步到掺铒光纤振荡器。这两个光振荡器之间的漂移在24小时内为3.3飞秒均方根（rms）。68兆赫兹的掺铒光纤振荡器被锁定到一个476兆赫兹的本地射频参考时钟，并作为主时钟通过稳定的光纤链路分发10飞秒级的定时信号。这种稳定的远程双色光到光同步是迈向用于自由电子激光器（FEL）的集成飞秒光纤定时分配系统的重要一步；它不需要X射线脉冲，并且使亚10飞秒光/ X射线泵浦-探测实验变得可行。
