Superconductivity in High-Entropy Antimonide M$_{1-x}$Pt$_x$Sb (M = equimolar Ru, Rh, Pd, and Ir)

Daigorou Hirai; Naoto Uematsu; Koh Saitoh; Naoyuki Katayama; Koshi Takenaka

doi:10.1021/acs.inorgchem.3c01364

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arXiv · 2503.23692

Superconductivity in High-Entropy Antimonide M$_{1-x}$Pt$_x$Sb (M = equimolar Ru, Rh, Pd, and Ir)

Daigorou Hirai·Naoto Uematsu·Koh Saitoh·Naoyuki Katayama·Koshi Takenaka

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Abstract

The high-entropy concept was applied to the synthesis of transition-metal antimonides, M1-xPtxSb (M = equimolar Ru, Rh, Pd, and Ir). High-entropy antimonide samples crystallized in a pseudo-hexagonal NiAs-type crystal structure with a P63/mmc space group were successfully synthesized through a conventional solid-state reaction and subsequent quenching. A detailed investigation of the composition and equilibration conditions confirmed the reversible phase transition between a multi-phase state at low temperature and an entropy-driven single-phase solid solution at high temperatures. Electrical resistivity, magnetization, and heat capacity measurements of single-phase M1-xPtxSb (x = 0.2) samples revealed a bulk superconducting transition at 2.15(2) K. This study demonstrates that the high-entropy concept provides numerous opportunities for the discovery of new functional materials such as superconductors.

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Daigorou Hirai, Naoto Uematsu, Koh Saitoh, Naoyuki Katayama, Koshi Takenaka. 2025-03-31. Superconductivity in High-Entropy Antimonide M$_{1-x}$Pt$_x$Sb (M = equimolar Ru, Rh, Pd, and Ir). https://doi.org/10.1021/acs.inorgchem.3c01364

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