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Measurements of 25Mg+ and 27Al+ magnetic constants for improved ion clock accuracy



Samuel M. Brewer, Jwo-Sy Chen, Aaron M. Hankin, Ethan Clements, Chin-wen Chou, Kyle Beloy, Will McGrew, Xiaogang Zhang, Robert J. Fasano, Daniele Nicolodi, Holly Leopardi, Tara Fortier, Scott Diddams, Andrew Ludlow, David J. Wineland, David Leibrandt, David Hume


We have measured the quadratic Zeeman coefficient for the 3P0 excited electronic state in 27Al+, C2=-71.944(24) MHz/T2 and the hyperfine constant of the 25Mg+ 2S1/2 ground electronic state, Ahfs = -596 254 250.981(45) Hz, with improved uncertainties. Both constants are relevant to the evaluation of the 27Al+ quantum-logic clock accuracy. The measurement of C2 is in agreement with a previous measurement and a new calculation at the 1 sigma level. The measurement of Ahfs is in good agreement with a recent measurement and differs from a previously published result by approximately 2 sigma. With the improved value for Ahfs, we deduce an improved value for the nuclear-to-electronic g-factor ratio gI/gJ = 9.299 308 358(60) X 10-5 and the nuclear g-factor for the free 25Mg+ ion gI' = 1.861 957 83(28) X 10-4.
Physical Review A


Atomic clocks, lattice clocks, optical clocks, Precision Measurements, Trapped ions


Brewer, S. , Chen, J. , Hankin, A. , Clements, E. , Chou, C. , Beloy, K. , McGrew, W. , Zhang, X. , Fasano, R. , Nicolodi, D. , Leopardi, H. , Fortier, T. , Diddams, S. , Ludlow, A. , Wineland, D. , Leibrandt, D. and Hume, D. (2019), Measurements of <sup>25</sup>Mg<sup>+</sup> and <sup>27</sup>Al<sup>+</sup> magnetic constants for improved ion clock accuracy, Physical Review A, [online], (Accessed June 20, 2024)


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Created July 15, 2019, Updated April 23, 2021