Perturbation Analysis of Pairing Symmetry and Transition Temperature in Quasi-One-Dimensional Organic Superconductors

Abstract

We investigate pairing symmetry in quasi-one-dimensional organic superconductors, solving Eliashberg's equation within third order perturbation theory for a repulsive Hubbard model. According to the calculation results, spin-singlet state is expected to give higher transition temperature than spin-triplet one and the vertex corrections reduce the transition temperature for the spin-singlet case. It is shown that the contributions of antiferromagnetic spin fluctuations dominate strongly the momentum dependence of the effective pairing interaction for both of the spin-triplet and the spin-singlet pairing cases.