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Exact Bond-Located Spin Ground State in the Hubbard Chain with Off-Diagonal Coulomb Interactions

Kazuhito Itoh·Masaaki Nakamura·Norihiro Muramoto
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Abstract

We show the existence of an exact ground state in certain parameter regimes of one-dimensional half-filled extended Hubbard model with site-off-diagonal interactions. In this ground state, the bond-located spin correlation exhibits a long-range order. In the case when the spin space is SU(2) symmetric, this ground state degenerates with higher spin states including a fully ferromagnetic state. We also discuss the relation between the exact bond-ordered ground state and the critical bond-spin-density-wave phase.

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Kazuhito Itoh, Masaaki Nakamura, Norihiro Muramoto. 2001-02-27. Exact Bond-Located Spin Ground State in the Hubbard Chain with Off-Diagonal Coulomb Interactions. https://doi.org/10.1143/jpsj.70.1202

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