Cited by 174Advanced Frequency and Time StandardsScientific Measurement and Uncertainty EvaluationNetwork Time Synchronization Technologies

Towards a redefinition of the second based on optical atomic clocks

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Riehle, Fritz·2015·Comptes Rendus. Physique

Abstract

The rapid increase in accuracy and stability of optical atomic clocks compared to the caesium atomic clock as the primary standard of time and frequency asks for a future redefinition of the second in the International System of Units (SI). The status of the optical clocks based on either single ions in radio-frequency traps or on neutral atoms stored in an optical lattice is described, with special emphasis on the current work at the Physikalisch-Technische Bundesanstalt (PTB, Braunschweig, Germany). Besides the development and operation of different optical clocks with estimated fractional uncertainties in the 10 − 18 range, the supporting work on ultra-stable lasers as core elements and the means to compare remote optical clocks with transportable standards, optical fibres, or frequency ratios is reported. Finally, the conditions, methods and next steps are discussed, which are the prerequisites for a future redefinition of the second.

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Crossref · 10.1016/j.crhy.2015.03.012

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  • The work clears the path towards a redefinition of the SI second through regular and practical international comparisons of optical clocks.

    “Our work not only enables the above mentioned applications, but also clears the path towards a redefinition of the unit of time, the SI second2425 through regular and practical international comparisons of optical clocks.”

    From A clock network for geodesy and fundamental science (2016) · cites this paper as [24]

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  1. [63][63] P. Wolf, G. Petit, E. Peik, C. Tamm, H. Schnatz, B. Lipphardt, S. Weyers, R. Wynands, J.-Y. Richard, S. Bize, F. Chapelet, F. Pereira dos Santos, A. Clairon, Comparing high accuracy frequency standards via TAI, 20 th European Frequency and Time Forum, Braunschweig, ISBN 978-1-4673-2642-1, (2006) 476-485. www.eftf.org/proceedings/proceedingsEFTF2006.pdf. -

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Authors
Riehle, F.
Corresponding author
Riehle, Fritz
Venue
Comptes Rendus. Physique
Published
2015-06-01
Volume
16
Issue
5
Pages
506-515
ISSN
  • 1631-0705 (ISSN-L)
  • 1878-1535
OpenAlex
W1512386837
Cited by
174
References
65
Citations by year
2026: 11 · 2025: 12 · 2024: 13 · 2023: 21 · 2022: 13 · 2021: 11 · 2020: 12 · 2019: 26 · 2018: 16 · 2017: 20 · 2016: 19
FWCI
9.27
Type
journal article
Language
en
Open access
Locations
  • Comptes Rendus Physique (publishedVersion)
  • arXiv (Cornell University) (submittedVersion)
  • Physical Reports (submittedVersion)
  • arXiv (Cornell University)
Funders
DFG (RTG 1729)
Topics
  • Physical Sciences › Physics and Astronomy › Atomic and Molecular Physics, and Optics › Advanced Frequency and Time Standards
  • Social Sciences › Decision Sciences › Statistics, Probability and Uncertainty › Scientific Measurement and Uncertainty Evaluation
  • Physical Sciences › Computer Science › Computer Networks and Communications › Network Time Synchronization Technologies
Keywords
redefinition of the second, optical atomic clocks, SI units, radio-frequency trap, optical lattice clock, neutral atoms, fractional frequency uncertainty, ultra-stable lasers, frequency transfer, frequency ratio, cesium atomic clock, time and frequency standards

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