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arXiv · 0704.0717

Incommmensurability and unconventional superconductor to insulator transition in the Hubbard model with bond-charge interaction

A. A. Aligia·A. Anfossi·L. Arrachea·C. Degli Esposti Boschi·A. O. Dobry·C. Gazza·A. Montorsi·F. Ortolani·M. E. Torio
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Abstract

We determine the quantum phase diagram of the one-dimensional Hubbard model with bond-charge interaction X in addition to the usual Coulomb repulsion U at half-filling. For large enough X and positive U the model shows three phases. For large U the system is in the spin-density wave phase already known in the usual Hubbard model. As U decreases, there is first a spin transition to a spontaneously dimerized bond-ordered wave phase and then a charge transition to a novel phase in which the dominant correlations at large distances correspond to an incommensurate singlet superconductor.

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A. A. Aligia, A. Anfossi, L. Arrachea, C. Degli Esposti Boschi, A. O. Dobry, C. Gazza, A. Montorsi, F. Ortolani, M. E. Torio. 2007-11-14. Incommmensurability and unconventional superconductor to insulator transition in the Hubbard model with bond-charge interaction. https://doi.org/10.1103/physrevlett.99.206401

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