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Frequency Comparison of Al+ and Hg+ Optical Standards



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


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.
Proceedings Title
Proc. 2007 ICOLS Meeting
Conference Dates
June 24-29, 2007
Conference Location
Telluride, CO


atom trapping and cooling, quantum computation, quantum information processing, quantum superpositions, quantum-state engineering, trapped ions


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], (Accessed April 21, 2024)
Created June 24, 2007, Updated January 27, 2020