Quantum Control of Trapped Polyatomic Molecules for eEDM Searches

TL;DR

This paper demonstrates coherent quantum control of ultracold polyatomic molecules, specifically CaOH, enabling precise electron electric dipole moment (eEDM) measurements to probe physics beyond the Standard Model.

Contribution

It introduces a method for controlling quantum states in polyatomic molecules and applies it to eEDM searches, advancing quantum sensing capabilities.

Findings

Achieved coherent control of CaOH quantum states.

Demonstrated eEDM sensitive state preparation and measurement.

Extended coherence times using tunable, near-zero magnetic field states.

Abstract

Ultracold polyatomic molecules are promising candidates for experiments in quantum science, quantum sensing, ultracold chemistry, and precision measurements of physics beyond the Standard Model. A key, yet unrealized, requirement of these experiments is the ability to achieve full quantum control over the complex internal structure of the molecules. Here, we establish coherent control of individual quantum states in a polyatomic molecule, calcium monohydroxide (CaOH), and use these techniques to demonstrate a method for searching for the electron electric dipole moment (eEDM). Optically trapped, ultracold CaOH molecules are prepared in a single quantum state, polarized in an electric field, and coherently transferred into an eEDM sensitive state where an electron spin precession measurement is performed. To extend the coherence time of the measurement, we utilize eEDM sensitive states with tunable, near-zero magnetic field sensitivity. The spin precession coherence time is limited by AC Stark shifts and uncontrolled magnetic fields. These results establish a path for eEDM searches with trapped polyatomic molecules, towards orders-of-magnitude improved experimental sensitivity to time-reversal-violating physics.