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arXiv · 1706.00174

All-polarization-maintaining, single-port Er:fiber comb for high-stability comparison of optical lattice clocks

Noriaki Ohmae·Naoya Kuse·Martin E. Fermann·Hidetoshi Katori
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Abstract

All-polarization-maintaining, single-port Er:fiber combs offer long-term robust operation as well as high stability. We have built two such combs and evaluated the transfer noise for linking optical clocks. A uniformly broadened spectrum over 135-285 THz with a high signal-to-noise ratio enables the optical frequency measurement of the subharmonics of strontium, ytterbium, and mercury optical lattice clocks with the fractional frequency-noise power spectral density of $(1-2)\times 10^{-17}$ Hz$^{-1/2}$ at 1 Hz. By applying a synchronous clock comparison, the comb enables clock ratio measurements with $10^{-17}$ instability at 1 s, which is one order of magnitude smaller than the best instability of the frequency ratio of optical lattice clocks.

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Noriaki Ohmae, Naoya Kuse, Martin E. Fermann, Hidetoshi Katori. 2017-06-01. All-polarization-maintaining, single-port Er:fiber comb for high-stability comparison of optical lattice clocks. https://doi.org/10.7567/apex.10.062503

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