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arXiv · 0912.4137

Different orderings in the narrow-band limit of the extended Hubbard model on the Bethe lattice

F. Mancini·F. P. Mancini
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Abstract

We present the exact solution of a system of Fermi particles living on the sites of a Bethe lattice with coordination number z and interacting through on-site U and nearest-neighbor V interactions. This is a physical realization of the extended Hubbard model in the atomic limit. Within the Green's function and equations of motion formalism, we provide a comprehensive analysis of the model and we study the phase diagram at finite temperature in the whole model's parameter space, allowing for the on-site and nearest-neighbor interactions to be either repulsive or attractive. We find the existence of critical regions where charge ordering (V>0) and phase separation (V<0) are observed. This scenario is endorsed by the study of several thermodynamic quantities.

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F. Mancini, F. P. Mancini. 2009-12-21. Different orderings in the narrow-band limit of the extended Hubbard model on the Bethe lattice. https://doi.org/10.1140/epjb/e2010-00031-8

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