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arXiv · 1408.4989

Two-Way Optical Frequency Comparisons Over 100km Telecommunication Network Fibers

Anthony Bercy·Fabio Stefani·Olivier Lopez·Christian Chardonnet·Paul-Eric Pottie·Anne Amy-Klein
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Abstract

By using two-way frequency transfer, we demonstrate ultra-high resolution comparison of optical frequencies over a telecommunication fiber link of 100 km operating simultaneously digital data transfer. We first propose and experiment a bi-directional scheme using a single fiber. We show that the relative stability at 1 s integration time is 7 10^18 and scales down to 5 10^21. The same level of performance is reached when an optical link is implemented with an active compensation of the fiber noise. We also implement a real-time two-way frequency comparison over a uni-directional telecommunication network using a pair of parallel fibers. The relative frequency stability is 10^15 at 1 s integration time and reaches 2 10^17 at 40 000 s. The fractional uncertainty of the frequency comparisons was evaluated for the best case to 2 10^20. These results open the way to accurate and high resolution frequency comparison of optical clocks over intercontinental fiber networks.

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Anthony Bercy, Fabio Stefani, Olivier Lopez, Christian Chardonnet, Paul-Eric Pottie, Anne Amy-Klein. 2014-08-21. Two-Way Optical Frequency Comparisons Over 100km Telecommunication Network Fibers. https://doi.org/10.1103/physreva.90.061802

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