2004/02/13 by Takahiko Sasaki, T. Sasaki, P. Badica +7
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.str-el #cond-mat.supr-con
paper · pdf · doi:10.1143/jpsj.73.1131
published as J. Phys. Soc. Jpn. 73, 1131 (2004) · 4 pages, 4 figures
arxiv created 2004/02/13 · openalex publication_date 2004/05/15 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We report the in-plane resistivity and magnetic susceptibility of the layered cobalt oxide Na0.35CoO2⋅1.3H2O single crystal. The temperature dependence of the resistivity shows metallic behavior from room temperature to the superconducting transition temperature Tc of 4.5 K. Sharp resistive transition, zero resistivity and almost perfect superconducting volume fraction below Tc indicate the good quality and the bulk superconductivity of the single crystal. The upper critical field Hc2 and the coherence length ξ are obtained from the resistive transitions in magnetic field parallel to the c-axis and the ab-plane. The anisotropy of ξ, ξab / ξc = 12 nm/1.3 nm ≃ 9.2, suggests that this material is considered to be an anisotropic three dimensional superconductor. In the field parallel to the ab-plane, Hc2 seems to be suppressed to the value of Pauli paramagnetic limit. It may indicate the spin singlet superconductivity in the cobalt oxide.