Long-distance chronometric leveling with a portable optical clock

2023/09/26 by J. Grotti, I. Nosske, S. B. Koller +19 · 1 voice
Physics and Astronomy · #physics.atom-ph #quant-ph

paper · pdf · doi:10.1103/physrevapplied.21.l061001

arxiv published 2023/09/26 · arxiv updated 2024/11/29

Abstract

We have measured the geopotential difference between two locations separated by 457~km by comparison of two optical lattice clocks via an interferometric fiber link, utilizing the gravitational redshift of the clock transition frequency. The ⁸⁷Sr 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) \mathrmm² s^-2 agrees with an independent geodetic determination of 3915.88(0.30) \mathrmm² s^-2. The uncertainty of the chronometric geopotential difference is equivalent to an uncertainty of 27~cm in height.

Discussions

• Linking extremely stable optical clocks via an (suitably performative) "optical frequency transfer system" ( "stabilized fiber links" ) is complicated business -- obviously. While my question has been [stackexchange, 2 points]

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