Correlation between Tc and Lattice Parameters of Novel Superconducting NaxCoO2 yH2O

Abstract

We synthesized the five batches of the samples of the novel P3 type superconductor, Na${}_x$(H${}_3$O)${}_{y^{\prime }}$CoO${}_2\cdot y^{\prime \prime }$H${}_2$O, by the soft chemical process starting from $\alpha$-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.

arXiv comment2 pages, 2 figures, and 1 table, to be published in J. Phys. Soc. Jpn. 73 (9) with possible minor revisions

References in corpus (2)

• Unconventional Superconductivity and Nearly Ferromagnetic Spin Fluctuations in Na${}_x$CoO${}_2$$\cdot y$H${}_2$O
• Unconventional Upper- and Lower-Critical Fields and Normal-State Magnetic Susceptibility of the Novel Superconducting Compound $N{a}_{0.35}Co{O}_2\cdot 1.3H_{2}O$

Cited by in corpus (9)

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• Deformation of Electronic Structures Due to CoO6 Distortion and Phase Diagrams of NaxCoO2.yH2O
• CoO2-Layer-Thickness Dependence of Magnetic Properties and Possible Two Different Superconducting States in NaxCoO2.yH2O
• Specific Heat and Superfluid Density for Possible Two Different Superconducting States in NaxCoO2.yH2O
• Electron-phonon interaction dressed by electronic correlations near charge ordering as the origin for superconductivity in cobaltates
• Charge order and phonon renormalizations: Possible implications for cobaltates
• Unconventional superconductivity in NaxCoO2 yH2O
• 59Co-NMR Knight Shift of Superconducting Three-Layer NaxCoO2.yH2O