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arXiv · 2404.17363

Superconductivity with high upper critical field in an equiatomic high entropy alloy Sc-V-Ti-Hf-Nb

S. Jangid·P. K. Meena·R. K. Kushwaha·S. Srivastava·P. Manna·P. Mishra·S. Sharma·R. P. Singh
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Abstract

High-entropy alloy (HEA) superconductors have attracted significant attention due to their exceptional low-temperature mechanical and superconducting properties. We report the synthesis and thorough characterization of an equiatomic HEA superconductor with the composition Sc$_{0.20}$V$_{0.20}$Ti$_{0.20}$Hf$_{0.20}$Nb$_{0.20}$, crystallizing in a body-centered cubic crystal structure (Im3$\bar{m}$). Our investigation, using magnetization, transport, and heat capacity measurements, reveals the presence of weakly coupled, fully gapped superconductivity with a transition temperature of 4.17(3) K and the upper critical field exceeding the Pauli paramagnetic limit. The metallic nature, combined with a high upper critical field, positions it as a promising candidate for applications in superconducting devices.

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S. Jangid, P. K. Meena, R. K. Kushwaha, S. Srivastava, P. Manna, P. Mishra, S. Sharma, R. P. Singh. 2024-04-26. Superconductivity with high upper critical field in an equiatomic high entropy alloy Sc-V-Ti-Hf-Nb. https://arxiv.org/abs/2404.17363

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