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Phase Diagram of One-Dimensional Extended Hubbard Model at Half Filling

M. Tsuchiizu·A. Furusaki
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Abstract

We reexamine the ground-state phase diagram of the one-dimensional half-filled Hubbard model with on-site and nearest-neighbor repulsive interactions. We calculate second-order corrections to coupling constants in the g-ology to show that the bond-charge-density-wave (BCDW) phase exists for weak couplings in between the charge density wave (CDW) and spin density wave (SDW) phases. We find that the umklapp scattering of parallel-spin electrons destabilizes the BCDW state and gives rise to a bicritical point where the CDW-BCDW and SDW-BCDW continuous-transition lines merge into the CDW-SDW first-order transition line.

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M. Tsuchiizu, A. Furusaki. 2001-09-04. Phase Diagram of One-Dimensional Extended Hubbard Model at Half Filling. https://doi.org/10.1103/physrevlett.88.056402

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