Evaluating the Performances of the World's First Industrial Long-Haul Optical Fiber Link

This paper reports on the world's first optical frequency transfer link deployed and operated at an industrial level, and reaching state-of-the-art performances. In the frame of the REFIMEVE+ project supported in France by LPL (University of Paris 13) and SYRTE (LNE, Observatory of Paris) laboratories, a link between Paris and Lille is operational since October 2017 [1]. We report on a stability of the frequency transfer at the 10
^-20
level in a real field environment. The various measurement campaigns validate the repeatability and the reliability of the optical frequency transfer, but also the ease of use and the robustness of the technology that has been developed.