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Effects of Spin Fluctuations in Quasi-One-Dimensional Organic Superconductors

H. Kino·H. Kontani
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Abstract

We study the electronic states of quasi-one-dimensional organic conductors using the single band Hubbard model at half-filling. We treat the effects of the on-site Coulomb interaction by the fluctuation-exchange (FLEX) method, and calculate the phase diagram and physical properties. The calculated pressure dependence of the Neel temperature coincides well with the experimental one. We also show that a pseudogap is formed in the density of states near the chemical potential and that d-wave superconductivity appears next to the antiferromagnetic state. Moreover the NMR relaxation rate increases on cooling in the low-temperature region.

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H. Kino, H. Kontani. 1999-05-05. Effects of Spin Fluctuations in Quasi-One-Dimensional Organic Superconductors. https://doi.org/10.1143/jpsj.68.1481

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