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Enhancement of Jc by doping silver in grain boundaries of YBa2Cu3Oy polycrystals with solid-state diffusion method

C. H. Cheng·Y. Zhao
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Abstract

Grain boundaries (GBs) of YBa2Cu3Oy (YBCO) are preferentially doped with Ag by the solid-state diffusion method. The distribution of Ag is highly localized in the GB. As a result of the Ag doping, the Jc-H behavior of YBCO textured polycrystalline samples is significantly improved, and at 60 K and 7 T, Jc is tripled. It is proposed that Ag could partially replace the Cu in CuO2 planes near GBs, therefore reducing the geometric distortion of Cu-O bonds and making the effective GBs thinner.

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C. H. Cheng, Y. Zhao. 2003-02-06. Enhancement of Jc by doping silver in grain boundaries of YBa2Cu3Oy polycrystals with solid-state diffusion method. https://doi.org/10.1063/1.1539909

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