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  • Letter
  • Open Access

Long-distance chronometric leveling with a portable optical clock

J. Grotti1,†, I. Nosske1,†, S.B. Koller1, S. Herbers1, H. Denker2, L. Timmen2, G. Vishnyakova3, G. Grosche1, T. Waterholter1 et al.

A. Kuhl1, S. Koke1, E. Benkler1, M. Giunta3,4, L. Maisenbacher3, A. Matveev3, S. Dörscher1, R. Schwarz1, A. Al-Masoudi1, T.W. Hänsch3, Th. Udem3, R. Holzwarth3,4, and C. Lisdat1,*

  • *Corresponding author: christian.lisdat@ptb.de
  • †J.G. and I.N. contributed equally to this work.
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Phys. Rev. Applied 21, L061001 – Published 3 June, 2024

DOI: https://doi.org/10.1103/PhysRevApplied.21.L061001

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)m2s−2 agrees with an independent geodetic determination of 3915.88(0.30)m2s−2. The uncertainty of the chronometric geopotential difference is equivalent to an uncertainty of 27cm in height.

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Outline

Information

Phys. Rev. Applied 21, L061001– Published 3 June, 2024
  • Received 21 September 2023
  • Revised 29 April 2024
  • Accepted 1 May 2024
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