2005/08/22 by Kazuhiko Kuroki, Kuroki, Kazuhiko, Seiichiro Onari +7
Earth and Planetary Sciences · Physics and Astronomy · #Advanced Condensed Matter Physics #FOS: Physical sciences #High-pressure geophysics and materials #Physics of Superconductivity and Magnetism #Strongly Correlated Electrons (cond-mat.str-el) #cond-mat.str-el
paper · pdf · doi:10.48550/arxiv.cond-mat/0508482
5 pages, uses RevTeX
arxiv created 2005/08/22 · openalex publication_date 2005/08/22 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
Motivated by recent experiments and band calculation results, we investigate the possibility of superconductivity originating from the a1g band of NaxCoO2⋅ yH2O assuming the absence of eg' pockets. We adopt a single band U-V model that takes into account the local minimum of the a1g band dispersion at the Γ point. Using the fluctuation exchange method, we find that an s-wave pairing with a gap that changes sign between the inner and the outer Fermi surfaces is enhanced due to the coexistence of spin fluctuations at wave vectors bridging the two Fermi surfaces and the charge fluctuations near the K point. Possible relevance to the experimental results is discussed.