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arXiv:2105.03442 · Physical Review A

van der Waals interaction as the starting point for an effective field theory

Daniel Odell, Arnoldas Deltuva, Lucas Platter

Published Aug 4, 2021• 7 citations
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Abstract

We consider the system of three $^{4}\mathrm{He}$ atoms to assess whether a pure van der Waals potential can be used as a starting point for an effective field theory to describe three-body processes in ultracold atomic systems. Using a long-range van der Waals interaction in combination with short-distance two-body counterterms, we analyze the dependence of two- and three-body observables on the short-distance regulator that is required due to the singular nature of the van der Waals interaction. We benchmark our approach with results obtained with the realistic $^{4}\mathrm{He}\ensuremath{-}^{4}\mathrm{He}$ LM2M2 potential and find good agreement. We furthermore show that in this effective field theory approach no three-body force is required at leading order and that universal van der Waals physics leads to a universal correlation between three-body observables in the absence of an Efimov three-body parameter.

DOI
10.1103/physreva.104.023306

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