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arXiv · 2412.00775

Coherence of Symmetry-Protected Rotational Qubits in Cold Polyatomic Molecules

Maximilian Löw·Martin Ibrügger·Gerhard Rempe·Martin Zeppenfeld
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Abstract

Polar polyatomic molecules provide an ideal but largely unexplored platform to encode qubits in rotational states. Here, we trap cold (100-600 mK) formaldehyde (H$_2$CO) inside an electric box and perform a Ramsey-type experiment to observe long-lived (~100 $\mu$s) coherences between symmetry-protected molecular states with opposite rotation but identical orientation, representing a quasi-hidden molecular degree of freedom. As a result, the observed qubit is insensitive to the magnitude of an external electric field, and depends only weakly on magnetic fields. Our findings provide a basis for future quantum and precision experiments with trapped cold molecules.

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Maximilian Löw, Martin Ibrügger, Gerhard Rempe, Martin Zeppenfeld. 2024-12-01. Coherence of Symmetry-Protected Rotational Qubits in Cold Polyatomic Molecules. https://doi.org/10.1103/physrevlett.134.113402

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