Next generation of the electron's Electric Dipole Moment using trapped ThF$^{\mathrm{+}}$ molecular ions

ThF$^{\mathrm{+}}$ has been chosen to replace HfF$^{\mathrm{+}}$ in the next-generation JILA electron's Electric Dipole Moment (eEDM) measurement, because of two major advantages: (i) the eEDM-sensitive state ($^{\mathrm{3}}\Delta_{\mathrm{1}})$ is the ground state, which facilitates a long coherence time [1]; (ii) its effective electric field (35 GV/cm) is 50{\%} larger than that of HfF$^{\mathrm{+}}$, which promises a direct linear increase of the eEDM sensitivity [2]. In this poster, we present recent experimental progress towards the preparation of ThF$^{\mathrm{+}}$ in a specific eEDM sensitive state (a single m$_{\mathrm{F}}$ state of $^{\mathrm{3}}\Delta_{\mathrm{1}})$, and the efficient detection of the electron spin resonance signal by resonant enhanced multiphoton dissociation (REMPD) of molecular ions. [1] D. N. Gresh, K. C. Cossel, Y. Zhou, J. Ye, E. A. Cornell, Journal of Molecular Spectroscopy, 319 (2016), 1-9 [2] M. Denis, M. S. N{\o}rby, H. J. A. Jensen, A. S. P. Gomes, M. K. Nayak, S. Knecht, T. Fleig, New Journal of Physics, 17 (2015) 043005.