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"Superconductor"-insulator transitions in a Hubbard chain with nearest- neighbor and bond-charge interactions

A. A. Aligia·E. R. Gagliano
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Abstract

We consider a half-filled generalized Hubbard chain with electron-hole symmetric correlated hopping and on-site and nearest-neighbor repulsions U and V respectively. In addition to the insulating charge- and spin-density wave phases for large V and U respectively, we identify a phase with dominant superconducting correlations at large distances for small U and V. Using two Berry phases (one associated to the charge and the other to the spin degrees of freedom) as discrete order parameters, we construct a phase diagram for the three thermodynamic phases.

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A. A. Aligia, E. R. Gagliano. 1997-12-16. "Superconductor"-insulator transitions in a Hubbard chain with nearest- neighbor and bond-charge interactions. https://doi.org/10.1016/s0921-4534(98)00270-6

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