Collective rotational cat states of molecules in microwave cavities

Volker Karle; Florian Kluibenschedl; Mikhail Lemeshko; Vasil Rokaj

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arXiv · 2606.25815

Collective rotational cat states of molecules in microwave cavities

Volker Karle·Florian Kluibenschedl·Mikhail Lemeshko·Vasil Rokaj

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Abstract

We show theoretically that an ensemble of polar molecules coupled to a microwave cavity supports hybrid rotational-photonic cat states. The cavity couples to a symmetric rotor in the bright manifold of $N$ molecules with $\sqrt{N}$-enhancement. In the dispersive limit of the collective strong coupling regime, virtual multilevel transitions induce an effective Kerr nonlinearity, as confirmed by Wigner tomography and a Schrieffer-Wolff analysis, leading to parity-locked cat structure in the cavity sectors. Collective molecular rotations thus provide a new route to hybrid light-matter cat states.

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Volker Karle, Florian Kluibenschedl, Mikhail Lemeshko, Vasil Rokaj. 2026-06-24. Collective rotational cat states of molecules in microwave cavities. https://arxiv.org/abs/2606.25815

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