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Charge Ordering in the One-Dimensional Extended Hubbard Model: Implication to the TMTTF Family of Organic Conductors

Y. Shibata·S. Nishimoto·Y. Ohta
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Abstract

We study the charge ordering (CO) in the one-dimensional (1D) extended Hubbard model at quarter filling where the nearest-neighbor Coulomb repulsion and dimerization in the hopping parameters are included. Using the cluster mean-field approximation to take into account the effect of quantum fluctuations, we determine the CO phase boundary of the model in the parameter space at T=0 K. We thus find that the dimerization suppresses the stability of the CO phase strongly, and in consequence, the realistic parameter values for quasi-1D organic materials such as (TMTTF)$_2$PF$_6$ are outside the region of CO. We suggest that the long-range Coulomb interaction between the chains should persist to stabilize the CO phase.

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Y. Shibata, S. Nishimoto, Y. Ohta. 2001-09-21. Charge Ordering in the One-Dimensional Extended Hubbard Model: Implication to the TMTTF Family of Organic Conductors. https://doi.org/10.1103/physrevb.64.235107

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