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arXiv · 1010.0159

Hidden XY structure of the bond-charge Hubbard model

Marco Roncaglia·Cristian Degli Esposti Boschi·Arianna Montorsi
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Abstract

The repulsive one-dimensional Hubbard model with bond-charge interaction (HBC) in the superconducting regime is mapped onto the spin-1/2 XY model with transverse field. We calculate correlations and phase boundaries, realizing an excellent agreement with numerical results. The critical line for the superconducting transition is shown to coincide with the analytical factorization line identifying the commensurate-incommensurate transition in the XY model.

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Marco Roncaglia, Cristian Degli Esposti Boschi, Arianna Montorsi. 2010-10-01. Hidden XY structure of the bond-charge Hubbard model. https://doi.org/10.1103/physrevb.82.233105

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