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arXiv · 1603.05025

Ultra-stable optical frequency dissemination on a multi-access fibre network

Anthony Bercy·Olivier Lopez·Paul-Eric Pottie·Anne Amy-Klein
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Abstract

We report the dissemination of an ultrastable optical frequency signal to two distant users simultaneously using a branching network. The ultrastable signal is extracted along a main fibre link; it is optically tracked with a narrow-linewidth laser diode, which light is injected in a secondary link. The propagation noise of both links is actively compensated. We implement this scheme with two links of 50-km fibre spools, the extraction being setup at the mid-point of the main link. We show that the extracted signal at the end of the secondary link exhibits fractional frequency instability of 1.4x10-15 at 1-s measurement time, almost equal to the 1.3x10-15 instability of the main link output end. The long-term instabilities are also very similar, at a level of 3-5x10-20 at 3x104-s integration time. We also show that the setting up of this extraction device, or a simpler one, at the main link input, can test the proper functioning of the noise rejection on this main link. This work is a significant step towards a robust and flexible ultra-stable network for multi-users dissemination.

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Anthony Bercy, Olivier Lopez, Paul-Eric Pottie, Anne Amy-Klein. 2016-03-16. Ultra-stable optical frequency dissemination on a multi-access fibre network. https://doi.org/10.1007/s00340-016-6463-3

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