Going beyond the new JILA eEDM result with a multiplexed experiment using ThF⁺

The Standard Model of particle physics is one of the most successful models that we use to describe the universe, yet it is known to be incomplete. Substantial efforts on the theoretical front introduce new physics through extensions of the Standard Model, and these new physics models make predictions on the value of the electric dipole moment of the electron (eEDM). Measurements of (or improved limit on) the eEDM places constraints on these new theories. The eEDM experiments at JILA take advantage of the long trapping time of ions to tap the long coherence times of the eEDM-sensitive states in our molecular ions of choice: HfF⁺ and ThF⁺. The recently concluded experiment using HfF⁺ [1,2] is an upgraded version of our 2017 experiment [3], using a bigger trap for more ions, amongst other improvements for better statistics. The upcoming experiment using ThF⁺ has recently completed spectroscopy of the molecule [4-6], and we are now setting up a prototype experiment to demonstrate the much longer coherence times promised to us by the eEDM-sensitive ground state in ThF⁺ [4,6]. We repoprt on progress towards observation of long coherence times in ThF⁺.

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[4] D. N. Gresh, K. C. Cossel, Y. Zhou, J. Ye, and E. A. Cornell, J. Mol. Spectrosc. 319, 1 (2016)

[5] Y. Zhou, K. B. Ng, L. Cheng, D. N. Gresh, R. W. Field, J. Ye, and E. A. Cornell, J. Mol. Spectrosc. 358, 1 (2019)

[6] K. B. Ng, Y. Zhou, L. Cheng, N. Schlossberger, S. Y. Park, T. S. Roussy, L. Caldwell, Y. Shagam, A. J. Vigil, E. A. Cornell, and J. Ye, Phys. Rev. A 105, 022823 (2022)