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Frequency Comparison of Two High-Accuracy Al+ Optical Clocks

Published

Author(s)

Chin-Wen Chou, David Hume, J.C. Koelemeij, David J. Wineland, Till P. Rosenband

Abstract

We have constructed an optical clock with a fractional frequency inaccuracy of 8.6e-18, based on quantum logic spectroscopy of an Al+ ion. A simultaneously trapped Mg+ ion serves to sympathetically laser-cool the Al+ ion and detect its quantum state. The frequency of the 1S0->3P0 clock transition is compared to that of a previously constructed Al+ optical clock with a statistical measurement uncertainty of 7.0e-18. The two clocks exhibit a relative stability of 2.8e-15/ sqrt(tau), and a fractional frequency difference of -1.8e-17, consistent with the accuracy limit of the older clock.
Citation
Physical Review Letters
Volume
104

Keywords

atomic clock, optical clock, high accuracy, aluminum ion, quantum logic
Created February 17, 2010, Updated February 19, 2017