The current limit on the electron's electric dipole moment, |de|<8.7×10-29 ecm (90% confidence), was set using the molecule thorium monoxide (ThO) in the J=1 rotational level of its H3Δ1 electronic state [J. Baron et al., Science 343, 269 (2014)SCIEAS0036-807510.1126/science.1248213] . This state in ThO is very robust against systematic errors related to magnetic fields or geometric phases, due in part to its Ω-doublet structure. These systematics can be further suppressed by operating the experiment under conditions where the g-factor difference between the Ω doublets is minimized. We consider the g factors of the ThO H3Δ1 state both experimentally and theoretically, including dependence on Ω doublets, the rotational level, and the external electric field. The calculated and measured values are in good agreement. We find that the g-factor difference between Ω doublets is smaller in J=2 than in J=1 and reaches zero at an experimentally accessible electric field. This means that the H,J=2 state should be even more robust against a number of systematic errors compared to H,J=1.
|Original language||English (US)|
|Journal||Physical Review A - Atomic, Molecular, and Optical Physics|
|State||Published - Jun 11 2014|
ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics