Superconductivity in a layered cobalt oxyhydrate Na0.31CoO2·1.3H2O

  title={Superconductivity in a layered cobalt oxyhydrate Na0.31CoO2·1.3H2O},
  author={Guanghan Cao and Chun-mu Feng and Yi Xu and Wen Lu and Jingqin Shen and Minghu Fang and Zhuang Xu},
  journal={Journal of Physics: Condensed Matter},
We report the electrical, magnetic and thermal measurements on a layered cobalt oxyhydrate Na0.31CoO2·1.3H2O. Bulk superconductivity at 4.3 K has been confirmed; however, the measured superconducting fraction is relatively low probably due to the sample's intrinsic two-dimensional characteristic. The compound exhibits weak-coupled and extreme type-II superconductivity with an average energy gap Δa(0) and a Ginzburg–Landau parameter κ of ~0.50 meV and 140, respectively. The temperature… Expand


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