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Hubbard Model on Decorated Lattices

C. D. Batista·B. S. Shastry
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Abstract

We introduce a family of lattices for which the Hubbard model and its natural extensions can be quasi-exactly solved, i.e. solved for the ground and low energy states. In particular, we show rigorously that the ground state of the Hubbard model with off-site Coulomb repulsions on a decorated Kagomè lattice is an ordered array of local currents. The low energy theory describing this chiral state is an $S=1/2$ XY model, where each spin degree of freedom represents the two possible chiralities of each local current.

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C. D. Batista, B. S. Shastry. 2003-07-31. Hubbard Model on Decorated Lattices. https://doi.org/10.1103/physrevlett.91.116401

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