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Microscopic theory of spin-triplet $f$-wave pairing in quasi-1D organic superconductors

Y. Tanaka·K. Kuroki
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Abstract

We present a microscopic theory of fluctuation-mediated pairing mechanism in organic superconductors ${(TMTSF)}_{2}X$, where the experimentally observed coexistence of $2k_{F}$ charge fluctuation and $2k_{F}$ spin fluctuation is naturally taken into account. We have studied, within the random phase approximation, the extended Hubbard model at quarter-filling on a quasi-one-dimensional lattice, where we consider the off-site repulsive interaction up to third next nearest neighbors along with the on-site repulsion. The results show that spin-triplet $f$-wave-like pairing can be realized in this system, dominating over singlet d-wave-like pairing, if $2k_F$ spin and $2k_F$ charge fluctuations coexist.

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Y. Tanaka, K. Kuroki. 2004-02-27. Microscopic theory of spin-triplet $f$-wave pairing in quasi-1D organic superconductors. https://doi.org/10.1103/physrevb.70.060502

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