arXiv 0807.40042008-07cond-mat.str-el

Finite-Temperature Phase Diagram of Quasi-One-Dimensional Molecular Conductors: Quantum Monte Carlo Study

Yuichi Otsuka, Hitoshi Seo, Yukitoshi Motome, Takeo Kato

备注：: Corrected typos
发表信息：: J. Phys. Soc. Jpn. Vol. 77, 113705 (2008)
DOI：: 10.1143/JPSJ.77.113705

英文摘要：

Finite-temperature phase transitions in quasi-one-dimensional quarter-filled systems are investigated by the extended Hubbard model with electron-lattice coupling. Using a quantum Monte Carlo method combined with the inter-chain mean-field approximation, we clarify competing and coexisting behaviors among charge ordering, dimer Mott, and spin-Peierls states. It is pointed out that an anharmonicity of lattice distortions plays an important role in multi-critical behaviors. The results are compared with experimental data for quasi-one-dimensional molecular conductors such as DCNQI and TMTTF compounds.

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