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The optical calcium frequency standards of PTB and NIST

Published

Author(s)

U Sterr, C Degenhardt, H Stoehr, Ch. Lisdat, H Schnatz, J Helmcke, F Riehle, G Wilpers, Christopher W. Oates, Leo W. Hollberg

Abstract

We describe the current status of the optical calcium frequency standard with laser-cooled neutral atoms realized in two different laboratories for the purpose of developing a possible future optical atomic clock. Frequency measurements performed at PTB and NIST make the frequency of the clock transition of 40}Ca one of the best known optical frequencies (relative uncertainty 1.2 x 10u-14}) and agree in both laboratories to well within their respective uncertainties. Prospects for orders of magnitude improvement in the standard look feasible.
Citation
Comptes Rendus Mathematique
Volume
5
Issue
8

Keywords

atomic clock, laser spectroscopy, optical frequency standard

Citation

Sterr, U. , Degenhardt, C. , Stoehr, H. , Lisdat, C. , Schnatz, H. , Helmcke, J. , Riehle, F. , Wilpers, G. , Oates, C. and Hollberg, L. (2004), The optical calcium frequency standards of PTB and NIST, Comptes Rendus Mathematique, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=50037 (Accessed May 29, 2024)

Issues

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Created November 4, 2004, Updated October 12, 2021