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Trap-induced ac Zeeman shift of the thorium-229 nuclear clock frequency



Kyle Beloy


We examine the effect of a parasitic rf magnetic field, attributed to ion trapping, on the highly anticipated nuclear clock based on $^229}$Th$^3+}$ [C. J. Campbell \it et al.}, Phys.\ Rev.\ Lett.\ 108, 120802 (2012)]. The rf magnetic field induces an ac Zeeman shift to the clock frequency. As we demonstrate, this shift threatens to be the dominant systematic frequency shift for the clock, exceeding other systematic frequency shifts and the projected systematic uncertainty of the clock by orders of magnitude. We propose practical means to suppress or eliminate this shift.
Physical Review Letters


atomic clock, nuclear clock


Beloy, K. (2023), Trap-induced ac Zeeman shift of the thorium-229 nuclear clock frequency, Physical Review Letters, [online], (Accessed June 16, 2024)


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Created March 8, 2023, Updated June 21, 2023