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arXiv · 0904.3398

Phase competitions and coexistences in quasi-one-dimensional molecular conductors: exact diagonalization study

Yuichi Otsuka·Hitoshi Seo·Yukitoshi Motome·Takeo Kato
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Abstract

We investigate ground state properties of a quasi-one-dimensional electron-lattice coupled model for quarter-filled molecular conductors. The effective one-dimensional extended Hubbard model coupled to adiabatic lattice degree of freedom is derived by the inter-chain mean-field approximation and solved by Lanczos exact diagonalization method. We find that the critical behavior among lattice tetramerized states with different charge-lattice ordered patterns is sensitively affected by the inter-chain Coulomb interaction, lattice anharmonicity, and intrinsic dimerization. This indicates a subtle balance between these states originating from strong correlation and reduced dimensionality.

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Yuichi Otsuka, Hitoshi Seo, Yukitoshi Motome, Takeo Kato. 2009-04-22. Phase competitions and coexistences in quasi-one-dimensional molecular conductors: exact diagonalization study. https://doi.org/10.1016/j.physb.2008.11.060

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