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Effect of Hydrostatic Pressure on the Superconductivity in NaxCoO2.yH2O

B. Lorenz·J. Cmaidalka·R. L. Meng·C. W. Chu
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Abstract

The effect of hydrostatic pressure on the superconducting transition temperature of Na{0.35}CoO{2}.yH{2}O was investigated by ac susceptibility measurements up to 1.6 GPa. The pressure coefficient of T{c} is negative and the dependence T{c}(p) is nonlinear over the pressure range investigated. The magnitude of the average dlnT{c}/dp=-0.07 GPa^{-1} is comparable to the pressure coefficient of electron-doped high-T{c} copper oxide superconductors with a similar value of T{c}. Our results provide support to the assumption of two-dimensional superconductivity in Na{0.35}CoO{2}.yH{2}O, which is similar to the cuprate systems, and suggest that intercalation of larger molecules may lead to an enhancement of T{c}.

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B. Lorenz, J. Cmaidalka, R. L. Meng, C. W. Chu. 2003-10-08. Effect of Hydrostatic Pressure on the Superconductivity in NaxCoO2.yH2O. https://doi.org/10.1103/physrevb.68.132504

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