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Frequency Comparison of Al+ and Hg+ Optical Standards
Published
Author(s)
Till P. Rosenband, David Hume, Anders Brusch, Luca Lorini, P. O. Schmidt, Tara M. Fortier, Jason Stalnaker, Scott A. Diddams, Nathan R. Newbury, W Swann, Windell Oskay, Wayne M. Itano, David J. Wineland, James C. Bergquist
Abstract
We compare the frequencies of two single ion frequency standards: 27Al+ and 199Hg+. Systematic fractional frequency uncertainties of both standards are below 10-16, and the statistical measurement uncertainty is below 5 x 10-17. Recent ratio measurements show a reproducibility that is better than 10-16.
atom trapping and cooling, quantum computation, quantum information processing, quantum superpositions, quantum-state engineering, trapped ions
Citation
Rosenband, T.
, Hume, D.
, Brusch, A.
, Lorini, L.
, Schmidt, P.
, Fortier, T.
, Stalnaker, J.
, Diddams, S.
, Newbury, N.
, Swann, W.
, Oskay, W.
, Itano, W.
, Wineland, D.
and Bergquist, J.
(2007),
Frequency Comparison of Al<sup>+</sup> and Hg<sup>+</sup> Optical Standards, Proc. 2007 ICOLS Meeting, Telluride, CO, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=50640
(Accessed October 17, 2025)