2003/04/23 by Hiroya Sakurai, Kazunori Takada, Shunsuke Yoshii +4 · 3 citations
Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Magnetic and transport properties of perovskites and related materials #Physics of Superconductivity and Magnetism #cond-mat.supr-con
paper · pdf · doi:10.1103/physrevb.68.132507
4 pages, 4figures. Submitted to Phys. Rev. Lett
arxiv created 2003/04/23 · openalex publication_date 2003/10/16 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
Magnetic properties of the layered superconductor, Na0.35CoO2\ensuremath⋅1.3H2O have been investigated. From the temperature dependence and field dependence of the magnetization, the superconducting transition temperature, as well as upper- and lower-critical fields have been estimated to be TC=4.6K, HC2(0)=61.0T and HC1(0)=28.1Oe, respectively. These values give quite unusual phenomenological parameters, i.e., coherent length, penetration depth and Ginzburg-Landau parameter of \ensuremathξ=2.32nm, \ensuremathλ=5.68\ifmmode×\else\texttimes\fi102nm, and \ensuremathκ\ensuremath≡\ensuremathλ/\ensuremathξ=244, respectively, suggesting an unconventional nature of superconductivity. Additionally, the magnetic susceptibility above TC and the magnetization curve up to 54 T are also reported.