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arXiv · 1103.2962

FFLO oscillations and magnetic domains in the Hubbard model with off-diagonal Coulomb repulsion

A. Anfossi·C. Degli Esposti Boschi·A. Montorsi
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Abstract

We observe the effect of non-zero magnetization m onto the superconducting ground state of the one dimensional repulsive Hubbard model with correlated hopping X. For t/2 < X < 2t/3, the system first manifests Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) oscillations in the pair-pair correlations. For m = m1 a kinetic energy driven macroscopic phase separation into low-density superconducting domains and high-density polarized walls takes place. For m > m2 the domains fully localize, and the system eventually becomes a ferrimagnetic insulator.

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A. Anfossi, C. Degli Esposti Boschi, A. Montorsi. 2011-12-27. FFLO oscillations and magnetic domains in the Hubbard model with off-diagonal Coulomb repulsion. https://doi.org/10.1088/1742-5468%2F2011%2F12%2Fp12014

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