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Structure of boson systems beyond the mean-field

O. Sørensen·D. V. Fedorov·A. S. Jensen
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Abstract

We investigate systems of identical bosons with the focus on two-body correlations. We use the hyperspherical adiabatic method and a decomposition of the wave function in two-body amplitudes. An analytic parametrization is used for the adiabatic effective radial potential. We discuss the structure of a condensate for arbitrary scattering length. Stability and time scales for various decay processes are estimated. The previously predicted Efimov-like states are found to be very narrow. We discuss the validity conditions and formal connections between the zero- and finite-range mean-field approximations, Faddeev-Yakubovskii formulation, Jastrow ansatz, and the present method. We compare numerical results from present work with mean-field calculations and discuss qualitatively the connection with measurements.

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O. Sørensen, D. V. Fedorov, A. S. Jensen. 2003-10-20. Structure of boson systems beyond the mean-field. https://doi.org/10.1088/0953-4075%2F37%2F1%2F006

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