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arXiv · 2511.11906

Lellouch-Lüscher relation for ultracold few-atom systems under confinement

Jing-Lun Li·Paul S. Julienne·Johannes Hecker Denschlag·José P. D'Incao
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Abstract

We derive an analog of the Lellouch-Lüscher (LL) relation for few-body bosonic systems, linking few-body scattering loss rates to the energies and widths of the corresponding harmonically trapped few-body states. Three-body numerical simulations show that the LL relation applies across a broad range of interaction strengths and energies and allows the determination of scattering rates within a single partial wave. Our work establishes a robust theoretical framework for understanding the role of the finite volume effect in few-body observables in optical lattice and tweezer experiments, enabling precise determination of multi-body scattering rates.

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Jing-Lun Li, Paul S. Julienne, Johannes Hecker Denschlag, José P. D'Incao. 2026-05-20. Lellouch-Lüscher relation for ultracold few-atom systems under confinement. https://doi.org/10.1103/pzlp-7k8d

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