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arXiv · 0803.3277

Virial theorems for trapped cold atoms

Félix Werner
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Abstract

We present a general virial theorem for quantum particles with arbitrary zero-range or finite-range interactions in an arbitrary external potential. We deduce virial theorems for several situations relevant to trapped cold atoms: zero-range interactions with and without Efimov effect, hard spheres, narrow Feshbach resonances, and finite-range interactions. If the scattering length $a$ is varied adiabatically in the BEC-BCS crossover, we find that the trapping potential energy as a function of $1/a$ has an inflexion point at unitarity.

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Félix Werner. 2008-03-22. Virial theorems for trapped cold atoms. https://doi.org/10.1103/physreva.78.025601

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