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Novel Charge Order and Superconductivity in Two-Dimensional Frustrated Lattice at Quarter Filling

Hiroshi Watanabe·Masao Ogata
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Abstract

Motivated by the various physical properties observed in $θ$-(BEDT-TTF)$_2$X, we study the ground state of extended Hubbard model on two-dimensional anisotropic triangular lattice at 1/4-filling with variational Monte Carlo method. It is shown that the nearest-neighbor Coulomb interaction enhances the charge fluctuation and it induces the anomalous state such as charge-ordered metallic state and the triplet next-nearest-neighbor $f$-wave superconductivity. We discuss the relation to the real materials and propose the unified view of the family of $θ$-(BEDT-TTF)$_2$X.

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Hiroshi Watanabe, Masao Ogata. 2006-02-23. Novel Charge Order and Superconductivity in Two-Dimensional Frustrated Lattice at Quarter Filling. https://doi.org/10.1143/jpsj.75.063702

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