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arXiv · 2102.12271

Synthesis of new high-entropy alloy-type Nb3 (Al, Sn, Ge, Ga, Si) superconductors

Aichi Yamashita·Tatsuma D. Matsuda·Yoshikazu Mizuguchi
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Abstract

Studies on high-entropy alloy (HEA) superconductors have recently been increasing, particularly in the fields of materials science and condensed matter physics. To contribute to research on new HEA-type superconductors, in our study we synthesized polycrystalline samples of A15-type superconductors of Nb3Al0.2Sn0.2Ge0.2Ga0.2Si0.2 (#1) and Nb3Al0.3Sn0.3Ge0.2Ga0.1Si0.1 (#2) with an HEA-type site by arc melting. Elemental and structural analyses revealed that the compositions of the obtained samples satisfied the HEA state criteria. Superconducting transitions were observed at 9.0 and 11.0 K for #1 and #2, respectively, in the temperature dependence of magnetization and electrical resistivity. Specific heat measurements revealed that the Sommerfeld coefficient, Debye temperature, and {\Delta}C/{\gamma}Tc for the obtained samples were close to those reported for conventional Nb3Sn family superconductors.

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Aichi Yamashita, Tatsuma D. Matsuda, Yoshikazu Mizuguchi. 2021-02-24. Synthesis of new high-entropy alloy-type Nb3 (Al, Sn, Ge, Ga, Si) superconductors. https://doi.org/10.1016/j.jallcom.2021.159233

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