Superconducting properties and electronic structure of CuAl2-type transition-metal zirconide Fe1-xNixZr2

Ryunosuke Shimada; Yuto Watanabe; Lorenzo Tortora; Giovanni Tomassucci; Muammer Yasin Hacisalihoǧlu; Hiroto Arima; Aichi Yamashita; Akira Miura; Chikako Moriyoshi; Naurang L. Saini; Yoshikazu Mizuguchi

doi:10.1016/j.jallcom.2024.177442

arXiv · 2405.04184

Superconducting properties and electronic structure of CuAl2-type transition-metal zirconide Fe1-xNixZr2

Ryunosuke Shimada·Yuto Watanabe·Lorenzo Tortora·Giovanni Tomassucci·Muammer Yasin Hacisalihoǧlu·Hiroto Arima·Aichi Yamashita·Akira Miura·Chikako Moriyoshi·Naurang L. Saini·Yoshikazu Mizuguchi

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Abstract

CuAl2-type transition-metal (Tr) zirconides are superconductor family, and the Tr-site element substitution largely modifies its transition temperature (Tc). Here, we synthesized polycrystalline samples of Fe1-xNixZr2 by arc melting. From magnetic susceptibility measurements, bulk superconductivity was observed for 0.4 < x < 0.8, and the highest Tc of 2.8 K was observed for x = 0.6. Specific heat measurements were also performed, bulk superconductivity was observed for 0.4 < x < 0.8, and the highest Tc of 2.6 K was observed for x = 0.6. The obtained superconductivity phase diagram exhibits dome-shaped trend, which is similar to unconventional superconductors, where magnetic fluctuations are essential for superconductivity. In addition, from the c/a lattice constant ratio analysis, we show the possible relationship between the suppression of bulk superconductivity in the Ni-rich compositions and a collapsed tetragonal transition.

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Ryunosuke Shimada, Yuto Watanabe, Lorenzo Tortora, Giovanni Tomassucci, Muammer Yasin Hacisalihoǧlu, Hiroto Arima, Aichi Yamashita, Akira Miura, Chikako Moriyoshi, Naurang L. Saini, Yoshikazu Mizuguchi. 2024-05-07. Superconducting properties and electronic structure of CuAl2-type transition-metal zirconide Fe1-xNixZr2. https://doi.org/10.1016/j.jallcom.2024.177442

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