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Correlation between Tc and Lattice Parameters of Novel Superconducting NaxCoO2 yH2O

H. Sakurai·K. Takada·T. Sasaki·F. Izumi·R. A. Dilanian·E. Takayama-Muromachi
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Abstract

We synthesized the five batches of the samples of the novel P3 type superconductor, Na$_{x}$(H$_{3}$O)$_{y'}$CoO$_{2}\cdot y''$H$_{2}$O, by the soft chemical process starting from $α$-NaCoO$_{2}$. The chemical and structural properties varied rather widely from batch to batch, with a result that $T_{c}$ varied from 4.6 K to 3.2 K. The magnetic susceptibility above $T_{c}$ shows upturn at low temperature as in the case of the P2 phase. The $T_{c}$ seems to be well correlated to the lattice parameters.

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H. Sakurai, K. Takada, T. Sasaki, F. Izumi, R. A. Dilanian, E. Takayama-Muromachi. 2004-08-19. Correlation between Tc and Lattice Parameters of Novel Superconducting NaxCoO2 yH2O. https://doi.org/10.1143/jpsj.73.2590

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