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arXiv · 2505.06763

Coordinated international comparisons between optical clocks connected via fiber and satellite links

Thomas Lindvall·Marco Pizzocaro·Rachel M. Godun·Michel Abgrall·Daisuke Akamatsu·Anne Amy-Klein·Erik Benkler·Nishant M. Bhatt·Davide Calonico·Etienne Cantin·Elena Cantoni·Giancarlo Cerretto·Christian Chardonnet·Miguel Angel Cifuentes Marin·Cecilia Clivati·Stefano Condio·E. Anne Curtis·Heiner Denker·Simone Donadello·Sören Dörscher·Chen-Hao Feng·Melina Filzinger·Thomas Fordell·Irene Goti·Kalle Hanhijärvi·H. Nimrod Hausser·Ian R. Hill·Kazumoto Hosaka·Nils Huntemann·Matthew Y. H. Johnson·Jonas Keller·Joshua Klose·Takumi Kobayashi·Sebastian Koke·Alexander Kuhl·Rodolphe Le Targat·Thomas Legero·Filippo Levi·Burghard Lipphardt·Christian Lisdat·Hongli Liu·Jérôme Lodewyck·Olivier Lopez·Maxime Mazouth-Laurol·Tanja E. Mehlstäubler·Alberto Mura·Akiko Nishiyama·Tabea Nordmann·Adam O. Parsons·Gérard Petit·Benjamin Pointard·Paul-Eric Pottie·Matias Risaro·Billy I. Robertson·Marco Schioppo·Haosen Shang·Kilian Stahl·Martin Steinel·Uwe Sterr·Alexandra Tofful·Mads Tønnes·Dang-Bao-An Tran·Jacob Tunesi·Anders E. Wallin·Helen S. Margolis
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Abstract

Optical clocks provide ultra-precise frequency references that are vital for international metrology as well as for tests of fundamental physics. To investigate the level of agreement between different clocks, we simultaneously measured the frequency ratios between ten optical clocks in six different countries, using fiber and satellite links. This is the largest coordinated comparison to date, from which we present a subset of 38 optical frequency ratios and an evaluation of the correlations between them. Four ratios were measured directly for the first time, while others had significantly lower uncertainties than previously achieved, supporting the advance towards a redefinition of the second and the use of optical standards for international time scales.

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Thomas Lindvall, Marco Pizzocaro, Rachel M. Godun, Michel Abgrall, Daisuke Akamatsu, Anne Amy-Klein, Erik Benkler, Nishant M. Bhatt, Davide Calonico, Etienne Cantin, Elena Cantoni, Giancarlo Cerretto, Christian Chardonnet, Miguel Angel Cifuentes Marin, Cecilia Clivati, Stefano Condio, E. Anne Curtis, Heiner Denker, Simone Donadello, Sören Dörscher, Chen-Hao Feng, Melina Filzinger, Thomas Fordell, Irene Goti, Kalle Hanhijärvi, H. Nimrod Hausser, Ian R. Hill, Kazumoto Hosaka, Nils Huntemann, Matthew Y. H. Johnson, Jonas Keller, Joshua Klose, Takumi Kobayashi, Sebastian Koke, Alexander Kuhl, Rodolphe Le Targat, Thomas Legero, Filippo Levi, Burghard Lipphardt, Christian Lisdat, Hongli Liu, Jérôme Lodewyck, Olivier Lopez, Maxime Mazouth-Laurol, Tanja E. Mehlstäubler, Alberto Mura, Akiko Nishiyama, Tabea Nordmann, Adam O. Parsons, Gérard Petit, Benjamin Pointard, Paul-Eric Pottie, Matias Risaro, Billy I. Robertson, Marco Schioppo, Haosen Shang, Kilian Stahl, Martin Steinel, Uwe Sterr, Alexandra Tofful, Mads Tønnes, Dang-Bao-An Tran, Jacob Tunesi, Anders E. Wallin, Helen S. Margolis. 2025-05-10. Coordinated international comparisons between optical clocks connected via fiber and satellite links. https://doi.org/10.1364/optica.561754

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