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arXiv · 2406.00618

Magnetic Feshbach resonances in ultracold atom-molecule collisions

Masato Morita·Maciej B. Kosicki·Piotr S. Zuchowski·Paul Brumer·Timur V. Tscherbul
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Abstract

We report numerically exact quantum scattering calculations on magnetic Feshbach resonances in ultracold, strongly anisotropic atom-molecule [Rb($^2$S) + SrF($^2\Sigma^+$)] collisions based on state-of-the-art ab initio potential energy surfaces. We find broad resonances mediated by the intermolecular spin-exchange interaction, as well as narrow resonances due to the intramolecular spin-rotation interaction, which are unique to atom-molecule collisions. Remarkably, the density of resonances in atom-molecule collisions is not much higher than that in atomic collisions despite the presence of a dense manifold of molecular rotational states, which can be rationalized by analyzing the adiabatic states of the collision complex.

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Masato Morita, Maciej B. Kosicki, Piotr S. Zuchowski, Paul Brumer, Timur V. Tscherbul. 2024-06-02. Magnetic Feshbach resonances in ultracold atom-molecule collisions. https://doi.org/10.1103/physreva.110.l021301

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