Hou Dong, Li Peng, Liu Cheng, Zhao Jianye, Zhang Zhigang
Department of Electronics, Peking University, Beijing, China.
Opt Express. 2011 Jan 17;19(2):506-11. doi: 10.1364/OE.19.000506.
We report a novel technique for highly stable transfer of a frequency comb over long optical fiber link. The technique implements an electronic compensation loop to cancel out the phase fluctuations that is introduced by the fiber. We utilized this technique to transfer a stable microwave frequency through a 20 km urban fiber link and an 80 km open air fiber link respectively. For the 20 km urban fiber link, the active compensation system reduced the phase fluctuation from 75 mrad (118 ps) to 4 mrad (6.3 ps) in 48 hours, and the frequency stability was improved by three orders of magnitude. For the 80 km open air fiber link, the active compensation system reduced the rms phase fluctuation from 580 mrad (914 ps) to 10 mrad (16 ps) in 24 hours, and the frequency stability was improved by two orders of magnitude.
我们报告了一种用于在长光纤链路上实现频率梳高度稳定传输的新技术。该技术实现了一个电子补偿环路，以抵消光纤引入的相位波动。我们利用此技术分别通过一条20公里的城市光纤链路和一条80公里的露天光纤链路传输稳定的微波频率。对于20公里的城市光纤链路，有源补偿系统在48小时内将相位波动从75毫弧度（118皮秒）降低到4毫弧度（6.3皮秒），频率稳定性提高了三个数量级。对于80公里的露天光纤链路，有源补偿系统在24小时内将均方根相位波动从580毫弧度（914皮秒）降低到10毫弧度（16皮秒），频率稳定性提高了两个数量级。
