高精度远距离光纤光学频率传递研究

The frequency transfer via optical fibers has demonstrated the unrivaled features of super-high frequency resolution and time resolution, which can provide a high-precision and real-time observation method for the large-scale precision measurement physics and high-tech applications. After the breakthrough of the fundamental principle and key techniques, the present research interests focus on the extending the distance, improving the precision and realization of optical frequency transfer network. This project will research on the influence of the nonlinear effect in the fiber on the optical coherent transfer and new approaches to build a more reliable cascaded fiber link. To overcome the limitation of the conventional point-to point transfer scheme, new topological network for optical frequency transfer will be under development. An optical frequency transfer link with multiple user ends based on an urban fiber link with total-length more than 500km will be demonstrated. Frequency transfer instability better than 1E-20 will be achieved within ten thousands seconds between the user ends. This project will prompt the future application of optical frequency transfer in the fields of precision measurement physics and related researches, in the meanwhile will contribute to the development of those fields.

基于光纤的光学频率传递具有超高的频率分辨率和时间分辨率，可以为与时空相关的、特别是广域范围的一些精密测量物理研究及高技术应用领域提供一种超高精度的、实时的观测手段。光纤光学频率传递在解决基本原理以及突破关键技术的基础上，正向超远距离、超高精度、网络化应用等方向发展，以满足相关领域的实际需求。本项目着眼于如何进一步提高传递距离、传递精度以及实现网络化传递与比对，研究光纤非线性效应对光学相干传递的影响，提出超远距离高可靠中继新方法，突破目前点对点传递限制，解决多用户网络化频率传递与比对的问题。预期在实地光纤传递网中演示总长大于500km、包含多用户节点的网络化光学频率传递与比对，万秒内在用户节点间实现传递与比对精度优于1E-20。通过本项目研究，将促进光纤光学频率传递在精密测量物理及相关领域的应用，推动相关研究及应用领域的发展。

基于光纤的光学频率传递具有超高的频率分辨率和时间分辨率，可以为与时空相关的、特别是广域范围的一些精密测量物理研究及高技术应用领域提供一种超高精度的、实时的观测手段。本项目围绕多用户网络化的光纤光学频率传递与比对，研究实现了通信波段自动化锁定的超稳光源，解决了超稳光源实际应用面临的主要技术困难；研究突破了超精度光纤相位噪声的探测及抑制技术，在百公里级光纤上实现了E-20量级的光学频率传递精度，可以满足我国异地光钟比对的精度需求；开展了适用于多用户网络化的基于两级EDFA的中继传递方案，中继传递精度国内领先，为网络化光频传递系统建立提供了技术支撑；自主提出并实验验证了基于本地测量的光学双向相位比对方案，200km光纤光频比对精度达到E-21量级，优于国际同类指标。