Milestones toward Next-Generation eEDM Measurement with Trapped ThF⁺ at JILA

The JILA electron electric dipole moment (eEDM) experiment reported the most precise measurement to date using trapped HfF⁺ molecular ions, with an eEDM result of ⋅  [1]. The next-generation JILA eEDM effort using ThF⁺ targets improved sensitivity by extending interrogation time and increasing ion counting statistics [2,3,4]. Here we present key milestones toward this goal: (i) a new trap/electrode design aimed at reducing field inhomogeneities, (ii) a new loading scheme to increase experimental duty cycle, and (iii) operation in regimes supporting longer coherence times at high ion number. As an additional control capability, we demonstrate localized π/2 pulses, necessary continuous operation. Finally, we describe ongoing work to determine the sign of the g-factor in the eEDM-sensitive state of ThF⁺.

Acknowledgement: This work was supported by the Gordon and Betty Moore Foundation, grant DOI 10.37807/GBMF13862, by the Alfred P. Sloan Foundation under Grant No. APSF 2025-79211, by AFOSR (FA9550-20-1-0323), by NSF PFC (PHY-2317149), by the National Institute of Standards and Technology, by a Marsico Chair of Excellence, by the Hertz Foundation (T.A.N.), and by the NSF GRFP (DGE-2040434) (T.A.N.).