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arXiv · 2012.11784

Orbital Variational Adiabatic Hyperspherical Method Applied to Bose-Einstein Condensates

Hyunwoo Lee·Chris H. Greene
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Abstract

A variational basis set motivated by mean-field theory is utilized to describe the Bose-Einstein condensate within the adiabatic hyperspherical coordinate framework. The simplest single-orbital variant of this treatment reproduces many of the ground state properties predicted by the Gross-Pitaevskii equation. But a multi-orbital improvement to the basis set yields a better representation of particle correlations and of the critical number where the condensate collapses for a negative two-body scattering length. The method also produces systematic deviations from Bogoliubov theory for the fundamental monopole excitation frequency.

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Hyunwoo Lee, Chris H. Greene. 2020-12-22. Orbital Variational Adiabatic Hyperspherical Method Applied to Bose-Einstein Condensates. https://doi.org/10.1103/physreva.103.023325

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