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Phase diagrams of half-filled 1D and 2D extended Hubbard model within COM

Adolfo Avella·Ferdinando Mancini
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Abstract

The half-filled extended Hubbard model, in one and two dimensions, is studied by means of the 2-pole approximation within the Composite Operator Method with the aim at improving the possibilities to describe some of the experimental features observed for quasi-1D organic superconductors and Cu-O planes of cuprates. The phase diagrams ($T$-$V$ and $V$-$U$) are analyzed with respect to the paramagnetic metal - paramagnetic insulator - charge ordered phase transitions. The relevant features of the diagrams (rank of the phase transitions, critical points, reentrant behavior) are discussed in detail.

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Adolfo Avella, Ferdinando Mancini. 2006-05-05. Phase diagrams of half-filled 1D and 2D extended Hubbard model within COM. https://doi.org/10.1016/j.jpcs.2005.10.040

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