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arXiv · 2010.09976

Improved Frequency Ratio Measurement with 87Sr and 171Yb Optical Lattice Clocks at NMIJ

Yusuke Hisai·Daisuke Akamatsu·Takumi Kobayashi·Kazumoto Hosaka·Hajime Inaba·Feng-Lei Hong·Masami Yasuda
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Abstract

We report improved frequency ratio measurement with $^{87}$Sr and $^{171}$Yb optical lattice clocks at the National Metrology Institute of Japan (NMIJ). The $^{87}$Sr optical lattice clock is enhanced with several major modifications and is re-evaluated with a reduced uncertainty of $1.1\times10^{-16}$. We employed a $^{171}$Yb optical lattice clock with an uncertainty of $4\times10^{-16}$ that was developed for contributing to International Atomic Time (TAI). The measurement result is $\nu_{\mathrm{Yb}}/\nu_{\mathrm{Sr}}$ = 1.207 507 039 343 338 58(49)$_{\mathrm{sys}}$(6)$_{\mathrm{stat}}$ with a fractional uncertainty of $4.1\times10^{-16}$, which is 3.4 times smaller than our previous measurement result.

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Yusuke Hisai, Daisuke Akamatsu, Takumi Kobayashi, Kazumoto Hosaka, Hajime Inaba, Feng-Lei Hong, Masami Yasuda. 2020-10-20. Improved Frequency Ratio Measurement with 87Sr and 171Yb Optical Lattice Clocks at NMIJ. https://doi.org/10.1088/1681-7575/abc104

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