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arXiv · 1910.04983

Hyperfine averaging by dynamic decoupling in a multi-ion lutetium clock

R. Kaewuam·T. R. Tan·K. J. Arnold·S. R. Chanu·Zhiqiang Zhang·M. D. Barrett
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Abstract

We propose and experimentally demonstrate a scheme which effects hyperfine averaging during a Ramsey interrogation of a clock transition. The method eliminates the need to average over multiple optical transitions, reduces the sensitivity of the clock to its environment, and reduces inhomogeneous broadening in a multi-ion clock. The method is compatible with auto-balanced Ramsey spectroscopy, which facilitates elimination of residual shifts due to imperfect implementation and ac Stark shifts from the optical probe. We demonstrate the scheme using correlation spectroscopy of the $^1S_0$-to-$^3D_1$ clock transition in a three-ion Lu+ clock. From the demonstration we are able to provide a measurement of the $^3D_1$ quadrupole moment, $Θ(^3D_1)=0.634(9)ea_0^2$.

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R. Kaewuam, T. R. Tan, K. J. Arnold, S. R. Chanu, Zhiqiang Zhang, M. D. Barrett. 2019-10-11. Hyperfine averaging by dynamic decoupling in a multi-ion lutetium clock. https://doi.org/10.1103/physrevlett.124.083202

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