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arXiv · 2309.14953

Long-distance chronometric leveling with a portable optical clock

J. Grotti·I. Nosske·S. B. Koller·S. Herbers·H. Denker·L. Timmen·G. Vishnyakova·G. Grosche·T. Waterholter·A. Kuhl·S. Koke·E. Benkler·M. Giunta·L. Maisenbacher·A. Matveev·S. Dörscher·R. Schwarz·A. Al-Masoudi·T. W. Hänsch·Th. Udem·R. Holzwarth·C. Lisdat
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Abstract

We have measured the geopotential difference between two locations separated by $457~\mathrm{km}$ by comparison of two optical lattice clocks via an interferometric fiber link, utilizing the gravitational redshift of the clock transition frequency. The $^{87}$Sr clocks have been compared side-by-side before and after one of the clocks was moved to the remote location. The chronometrically measured geopotential difference of $3918.1(2.6)\,\mathrm{m^2 \, s^{-2}}$ agrees with an independent geodetic determination of $3915.88(0.30)\,\mathrm{m^2 \, s^{-2}}$. The uncertainty of the chronometric geopotential difference is equivalent to an uncertainty of $27~\mathrm{cm}$ in height.

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J. Grotti, I. Nosske, S. B. Koller, S. Herbers, H. Denker, L. Timmen, G. Vishnyakova, G. Grosche, T. Waterholter, A. Kuhl, S. Koke, E. Benkler, M. Giunta, L. Maisenbacher, A. Matveev, S. Dörscher, R. Schwarz, A. Al-Masoudi, T. W. Hänsch, Th. Udem, R. Holzwarth, C. Lisdat. 2023-09-26. Long-distance chronometric leveling with a portable optical clock. https://doi.org/10.1103/physrevapplied.21.l061001

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