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Effects of Substituting Calcium for Yttrium on the Superconducting Properties of YBa2Cu3Oz Bulk Samples

E. K. Nazarova·A. J. Zaleski·A. L. Zahariev·A. K. Stoyanova-Ivanova·K. N. Zalamova
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Abstract

We report systematic studies of AC magnetic susceptibility and transport properties of Y(1-x)Ca(x)Ba2Cu3Oz bulk samples with 0\leq x\leq 0.4. Single phase materials, reduction of carrier concentration and decrease of Tc to 85 K were obtained at doping levels up to 20%. For Y0.7Ca0.3Ba2Cu3Oz sample the improvement of grains boundary transport and screening capabilities has been observed as a result of the optimal ratio between carrier concentration and impurity phase BaCuO2 presence. The appearence of bulk pinning and nonlinear effects starting at the highest temperature were detected also.

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E. K. Nazarova, A. J. Zaleski, A. L. Zahariev, A. K. Stoyanova-Ivanova, K. N. Zalamova. 2004-01-28. Effects of Substituting Calcium for Yttrium on the Superconducting Properties of YBa2Cu3Oz Bulk Samples. https://doi.org/10.1016/j.physc.2004.01.002

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