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Continuous configuration-interaction for condensates in a ring

Ofir E. Alon·Alexej I. Streltsov·Kaspar Sakmann·Lorenz S. Cederbaum
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Abstract

A continuous configuration-interaction approach for condensates in a ring is introduced. In its simplest form this approach utilizes for attractive condensates the Gross-Pitaevskii symmetry-broken solution and arrives at a ground-state of correct symmetry. Furthermore, the energy found is {\it lower} than the Gross-Pitaevskii one and, with increasing number of particles and/or strength of inter-particle interaction, is even {\it lower} than that accessed by tractable diagonalization of the many-body Hamiltonian. Implications also to excited states are briefly discussed.

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Ofir E. Alon, Alexej I. Streltsov, Kaspar Sakmann, Lorenz S. Cederbaum. 2004-02-25. Continuous configuration-interaction for condensates in a ring. https://doi.org/10.1209/epl%2Fi2004-10047-3

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