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Publication Citation: The optical calcium frequency standards of PTB and NIST

NIST Authors in Bold

Author(s): U Sterr; C Degenhardt; H Stoehr; Ch. Lisdat; H Schnatz; J Helmcke; F Riehle; G Wilpers; Christopher W. Oates; Leo W. Hollberg;
Title: The optical calcium frequency standards of PTB and NIST
Published: November 05, 2004
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
Pages: pp. 845 - 855
Keywords: atomic clock,laser spectroscopy,optical frequency standard
Research Areas: Physics
PDF version: PDF Document Click here to retrieve PDF version of paper (2MB)