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arXiv · 0712.1276

Superconductivity in the Three-Fold Charge-Ordered Metal of the Triangular-Lattice Extended Hubbard Model

Shotaro Morohoshi·Yoshiyuki Fukumoto
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Abstract

The quarter-filling extended Hubbard model on the triangular lattice is studied to explore pairing instability in the three-fold charge-ordered (CO) metal. We derive a second-order strong-coupling effective Hamiltonian of doped carriers into the three-fold CO insulator at electron density of $n=2/3$, and then study the $f$- and $d_{xy}$-wave superconductivities down to $n=1/2$ by using the BCS mean-field approximation. It is found that the triplet $f$-wave pairing is more stable than the $d_{xy}$-wave one. We also point out that this coexisting state of the charge ordering and superconductivity is possible to have critical temperature $T_c \sim 0.01 t$.

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Shotaro Morohoshi, Yoshiyuki Fukumoto. 2007-12-28. Superconductivity in the Three-Fold Charge-Ordered Metal of the Triangular-Lattice Extended Hubbard Model. https://doi.org/10.1143/jpsj.77.023708

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