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arXiv · 2309.00263

Multichannel quantum defect theory with a frame transformation for ultracold atom-molecule collisions in magnetic fields

Masato Morita·Paul Brumer·Timur V. Tscherbul
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Abstract

We extend the powerful formalism of multichannel quantum defect theory combined with a frame transformation to ultracold atom-molecule collisions in magnetic fields. By solving the coupled-channel equations with hyperfine and Zeeman interactions omitted at short range, the extended theory enables a drastically simplified description of the intricate quantum dynamics of ultracold molecular collisions in terms of a small number of short-range parameters. We apply the formalism to ultracold Mg + NH collisions in a magnetic field, achieving a 10$^4$-fold reduction in computational effort.

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Masato Morita, Paul Brumer, Timur V. Tscherbul. 2023-09-01. Multichannel quantum defect theory with a frame transformation for ultracold atom-molecule collisions in magnetic fields. https://doi.org/10.1103/physrevlett.133.093402

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