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arXiv · 0805.0982

The Role of the Exchange Interaction in the One-Dimensional $n$-Component Hubbard Model

E. Szirmai·Ö. Legeza·J. Sólyom
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Abstract

The commensurate $p/q$-filled $n$-component Hubbard chain was investigated by bosonization and high-precision density-matrix renormalization-group analysis. It was found that depending on the relation between the number of components $n$, and the filling parameter $q$, the system shows metallic or insulating behavior, and for special fillings bond-ordered (dimerized, trimerized, tetramerized etc.) ground state develops in the insulating phase. A mean-field analysis shows that this bond ordering is a direct consequence of the spin-exchange interaction, which plays a crucial role in the one-parameter Hubbard model -- not only for infinite Coulomb repulsion, but for intermediate values as well.

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E. Szirmai, Ö. Legeza, J. Sólyom. 2008-05-07. The Role of the Exchange Interaction in the One-Dimensional $n$-Component Hubbard Model. https://arxiv.org/abs/0805.0982

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