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arXiv · 0802.2811

Effective-interaction approach to the many-boson problem

J. Christensson·C. Forssén·S. Åberg·S. M. Reimann
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Abstract

We show that the convergence behavior of the many-body numerical diagonalization scheme for strongly interacting bosons in a trap can be significantly improved by the Lee-Suzuki method adapted from nuclear physics: One can construct an effective interaction that acts in a space much smaller than the original Hilbert space. In particular for short-ranged forces and strong correlations, the method offers a good estimate of the energy and the excitation spectrum, at a computational cost several orders of magnitude smaller than that required by the standard method.

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J. Christensson, C. Forssén, S. Åberg, S. M. Reimann. 2009-02-27. Effective-interaction approach to the many-boson problem. https://doi.org/10.1103/physreva.79.012707

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