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Beyond Fermi pseudopotential: a modified GP equation

Haixiang Fu·Yuzhu Wang·Bo Gao
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Abstract

We present an effective potential and the corresponding modified Gross-Pitaevskii equation that account for the energy dependence of the two-body scattering amplitude through an effective-range expansion. For the ground state energy of a trapped condensate, the theory leads to what we call a shape-dependent confinement correction that improves agreements with diffusion Monte Carlo calculations. The theory illustrates, for relatively strong confinement and/or high density, how the shape dependence on atom-atom interaction can come into play in a many-atom quantum system.

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Haixiang Fu, Yuzhu Wang, Bo Gao. 2003-02-17. Beyond Fermi pseudopotential: a modified GP equation. https://doi.org/10.1103/physreva.67.053612

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