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Optical frequency standards based on mercury and aluminum ions



Wayne M. Itano, James C. Bergquist, Anders Brusch, Scott A. Diddams, Tara M. Fortier, Thomas P. Heavner, Leo W. Hollberg, David Hume, Steven R. Jefferts, Luca Lorini, Thomas E. Parker, Till P. Rosenband, Jason Stalnaker


Single-trapped-ion frequency standards based on a 282 nm transition in 199Hg+ and on a 267 nm transition in 27Al+ have been developed at NIST over the past several years. Their frequencies are measured relative to each other and to the NIST primary frequency standard, the NIST-F1 cesium fountain, by means of a self-referenced femtosecond laser frequency comb. Both ion standards have demonstrated instabilities and inaccuracies below 10-16.
Proceedings Title
Proceedings of the SPIE, Conference 6673


aluminum, atomic clocks, frequency standards, ion traps, mercury


Itano, W. , Bergquist, J. , Brusch, A. , Diddams, S. , Fortier, T. , Heavner, T. , Hollberg, L. , Hume, D. , Jefferts, S. , Lorini, L. , Parker, T. , Rosenband, T. and Stalnaker, J. (2007), Optical frequency standards based on mercury and aluminum ions, Proceedings of the SPIE, Conference 6673, [online], (Accessed July 25, 2024)


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Created September 12, 2007, Updated January 27, 2020