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arXiv · 2001.08365

Synthesis of RE123 high-Tc superconductors with a high-entropy-alloy-type RE site

Yuta Shukunami·Aichi Yamashita·Yosuke Goto·Yoshikazu Mizuguchi
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Abstract

We have synthesized high-entropy-alloy-type (HEA-type) RE123 superconductors Y0.28Nd0.16Sm0.18Eu0.18Gd0.20Ba2Cu3O7-d and Y0.18La0.24Nd0.14Sm0.14Eu0.15Gd0.15Ba2Cu3O7-d with a superconducting transition temperature (Tc) exceeding 90 K. From comparison between HEA-type and conventional RE123 samples, we found that the mixing entropy at the rare earth site does not affect Tc and critical current density (Jc) of the RE123 samples. For all the examined samples, orthorhombicity was found to be an essential parameter for Tc and Jc. In the regime near orthorhombic-tetragonal boundary, Jc for the HEA-type sample was larger than that of conventional-type samples, which suggests that HEA-type RE123 may be useful to improve Jc in the structure with low orthorhombicity.

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Yuta Shukunami, Aichi Yamashita, Yosuke Goto, Yoshikazu Mizuguchi. 2020-01-23. Synthesis of RE123 high-Tc superconductors with a high-entropy-alloy-type RE site. https://doi.org/10.1016/j.physc.2020.1353623

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