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Water Content and Superconductivity in Na0.3CoO2*yH2O

J. Cmaidalka·A. Baikalov·Y. Y. Xue·R. L. Meng·C. W. Chu
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Abstract

We report here the correlation between the water content and superconductivity in Na0.3CoO2*yH2O under the influences of elevated temperature and cold compression. The x-ray diffraction of the sample annealed at elevated temperatures indicates that intergrowths exist in the compound at equilibrium when 0.6 < y < 1.4. Its low-temperature diamagnetization varies linearly with y, but is insensitive to the intergrowth, indicative of quasi-2D superconductivity. The Tc-onset, especially, shifts only slightly with y. Our data from cold compressed samples, on the other hand, show that the water-loss non-proportionally suppresses the diamagnetization, which is suggestive of weak links.

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J. Cmaidalka, A. Baikalov, Y. Y. Xue, R. L. Meng, C. W. Chu. 2003-08-15. Water Content and Superconductivity in Na0.3CoO2*yH2O. https://doi.org/10.1016/j.physc.2003.11.008

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