2003/10/24 by Akito Kobayashi, Yasuhiro Tanaka, Masao Ogata +1 · 2 citations
Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Organic and Molecular Conductors Research #Physics of Superconductivity and Magnetism #cond-mat.supr-con
paper · pdf · doi:10.1143/jpsj.73.1115
9 pages, 5 figures, submitted to Journal of the Phys. Soc. of Japan
arxiv created 2003/10/24 · openalex publication_date 2004/05/15 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We investigate the superconducting (SC) state in two-dimensional extended Hubbard model at a quarter-filling with the on-site repulsive interaction (U) and the nearest-neighbor one (V), which lead to the spin fluctuation and the charge fluctuation, respectively. The effect of the charge fluctuation on the onset of the SC state is calculated by estimating the pairing interaction within the random phase approximation. Solving the linearized Eliashberg equation with the anomalous self-energy as the function of both momentum and frequency, we examined the singlet SC state on the plane of U and V with the fixed temperature. We found a novel result that the SC state with the dxy symmetry retains for most parameters of U and V, although the pairing interaction changes the sign from repulsive one into attractive one with increasing V. The reentrant transition as the function of temperature occurs close to the onset of the SC state.