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arXiv · 2401.05958

Rotational-state dependence of interactions between polar molecules

Etienne F. Walraven·Tijs Karman
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Abstract

The long-range electrostatic interactions between molecules depend strongly on their relative orientation, which manifests as a rotational state dependence. Interactions between molecules in the same rotational quantum state are well-known attractive rotational van der Waals interactions. Interactions in rotational states that differ by one quantum show resonant dipole-dipole interactions. We show that where molecules are in rotational states that differ by more than one quantum, they exhibit repulsive van der Waals interactions. At temperatures below a millikelvin, this effect can reduce collisional loss by multiple orders of magnitude. These repulsive interactions lead to applications in quantum simulation and impurity physics with ultracold polar molecules.

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Etienne F. Walraven, Tijs Karman. 2024-01-11. Rotational-state dependence of interactions between polar molecules. https://doi.org/10.1103/physreva.109.043310

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