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arXiv · 0904.2679

Optical frequency transfer via 146 km fiber link with 10^{-19} relative accuracy

G. Grosche·O. Terra·K. Predehl·R. Holzwarth·B. Lipphardt·F. Vogt·U. Sterr·H. Schnatz
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Abstract

We demonstrate the long-distance transmission of an ultra-stable optical frequency derived directly from a state-of-the-art optical frequency standard. Using an active stabilization system we deliver the frequency via a 146 km long underground fiber link with a fractional instability of 3*10^{-15} at 1 s, which is close to the theoretical limit for our transfer experiment. The relative uncertainty for the transfer is below 1*10^{-19} after 30 000 seconds. Tests with a very short fiber show that noise in our stabilization system contributes fluctuations which are two orders of magnitude lower, namely 3*10^{-17} at 1 s, reaching 10^{-20} after 4000 s.

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G. Grosche, O. Terra, K. Predehl, R. Holzwarth, B. Lipphardt, F. Vogt, U. Sterr, H. Schnatz. 2009-04-17. Optical frequency transfer via 146 km fiber link with 10^{-19} relative accuracy. https://doi.org/10.1364/ol.34.002270

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