Mercury Hydroxide as a Promising Triatomic Molecule to Probe P,T-odd Interactions

TL;DR

This study identifies mercury hydroxide (HgOH) as a highly promising triatomic molecule for detecting the electron's electric dipole moment, showing enhanced sensitivity and feasible laser cooling methods compared to similar molecules.

Contribution

It introduces HgOH as a new candidate for eEDM experiments, demonstrating its superior effective electric field and potential for laser cooling, supported by theoretical calculations.

Findings

HgOH has a four-fold enhancement in effective electric field over YbOH.

The potential energy curve and electric dipole moment support experimental feasibility.

Laser cooling of HgOH is possible using techniques similar to HgF.

Abstract

In the quest to find a favourable triatomic molecule for detecting electric dipole moment of an electron (eEDM), we identify mercury hydroxide (HgOH) as an extremely attractive candidate from both experimental and theoretical viewpoints. Our calculations show that there is a four-fold enhancement in the effective electric field of HgOH compared to the recently proposed ytterbium hydroxide (YbOH) [Phys. Rev. Lett. 119, 133002 (2017)] for eEDM measurement. Thus, in the (010) bending state associated with the electronic ground state, it could provide better sensitivity than YbOH from a theoretical point of view. We have also investigated the potential energy curve and permanent electric dipole moment of HgOH, which lends support for its experimental feasibility. Moreover, we propose that it is possible to laser cool the HgOH molecule by adopting the same technique as that in the diatomic polar molecule, HgF, as shown in [Phys. Rev. A 99, 032502 (2019)].