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DOE OSTI · 3376374

Parity-doublet coherence times in optically trapped polyatomic molecules

Robichaud, Paige [Harvard University, Cambridge, MA (United States); Harvard-MIT Center for Ultracold Atoms, Cambridge, MA (United States)] (ORCID:0009000530551692)·Hallas, Christian [Harvard University, Cambridge, MA (United States); Harvard-MIT Center for Ultracold Atoms, Cambridge, MA (United States)] (ORCID:0000000308696500)·Tao, Junheng [Harvard University, Cambridge, MA (United States); Harvard-MIT Center for Ultracold Atoms, Cambridge, MA (United States)] (ORCID:0000000284369192)·Lee, Giseok [Harvard University, Cambridge, MA (United States); Harvard-MIT Center for Ultracold Atoms, Cambridge, MA (United States)]·Vilas, Nathaniel B. [Harvard University, Cambridge, MA (United States); Harvard-MIT Center for Ultracold Atoms, Cambridge, MA (United States)] (ORCID:0000000191751990)·Doyle, John M. [Harvard University, Cambridge, MA (United States); Harvard-MIT Center for Ultracold Atoms, Cambridge, MA (United States)]
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Abstract

Polyatomic molecules provide complex internal structures that are ideal for applications in quantum information science, quantum simulation and precision searches for physics beyond the standard model. A key feature of polyatomic molecules is the presence of parity-doublet states. These structures, which generically arise from the rotational and vibrational degrees of freedom afforded by polyatomic molecules, are a powerful feature to pursue diverse quantum science applications. Linear triatomic molecules contain ℓ-type parity-doublet states in the vibrational bending mode, which are predicted to exhibit robust coherence properties. Here we report optically trapped CaOH molecules prepared in ℓ-type parity-doublet states and realize a bare qubit coherence time of $T$$^{*}_{2}$, which is longer than the 0.36 s lifetime of the bending mode. We suppress differential Stark shifts by cancelling ambient electric fields using molecular spectroscopy and characterize parity-dependent trap shifts, which are found to limit the coherence time. Furthermore, the parity-doublet coherence times achieved in this work are a defining milestone for the use of polyatomic molecules in quantum science.

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Robichaud, Paige [Harvard University, Cambridge, MA (United States); Harvard-MIT Center for Ultracold Atoms, Cambridge, MA (United States)] (ORCID:0009000530551692), Hallas, Christian [Harvard University, Cambridge, MA (United States); Harvard-MIT Center for Ultracold Atoms, Cambridge, MA (United States)] (ORCID:0000000308696500), Tao, Junheng [Harvard University, Cambridge, MA (United States); Harvard-MIT Center for Ultracold Atoms, Cambridge, MA (United States)] (ORCID:0000000284369192), Lee, Giseok [Harvard University, Cambridge, MA (United States); Harvard-MIT Center for Ultracold Atoms, Cambridge, MA (United States)], Vilas, Nathaniel B. [Harvard University, Cambridge, MA (United States); Harvard-MIT Center for Ultracold Atoms, Cambridge, MA (United States)] (ORCID:0000000191751990), Doyle, John M. [Harvard University, Cambridge, MA (United States); Harvard-MIT Center for Ultracold Atoms, Cambridge, MA (United States)]. 2026-02-11. Parity-doublet coherence times in optically trapped polyatomic molecules. https://doi.org/10.1038/s41586-026-10133-2

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