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arXiv · 0708.2765

Doublon-Holon Binding Effects on Mott Transitions in Two-Dimensional Bose Hubbard Model

Hisatoshi Yokoyama·Masao Ogata
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Abstract

A mechanism of Mott transitions in a Bose Hubbard model on a square lattice is studied, using a variational Monte Carlo method. Besides an onsite correlation factor, we introduce a four-body doublon-holon factor into the trial state, which considerably improves the variational energy and can appropriately describe a superfluid-insulator transition. Its essense consists in binding (and unbinding) of a doublon to a holon in a finite short range, identical with the cases of fermions. The features of this transition are qualitatively different from those of Brinkman-Rice-type transitions.

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Hisatoshi Yokoyama, Masao Ogata. 2007-08-21. Doublon-Holon Binding Effects on Mott Transitions in Two-Dimensional Bose Hubbard Model. https://doi.org/10.1016/j.jpcs.2008.06.087

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