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arXiv · 2608.21273

Superconducting ground state study of Cr-based equiatomic high-entropy alloy through $\mu\text{SR}$

Sonika Jangid·Rhea Stewart·Adrian D. Hillier·R. P. Singh
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Abstract

High-entropy alloy superconductors, characterized by extreme chemical disorder and complex electronic environments, have attracted significant attention as model systems for exploring superconductivity in disordered materials. Here, we investigate a Cr-based equiatomic HEA, Cr-V-Ti-Nb-Ta, which contains a magnetic 3d element, providing an opportunity to examine the influence of magnetic elements on superconductivity in highly disordered systems. Despite expected magnetic pair-breaking, this alloy exhibits bulk type-II superconductivity with a transition temperature of $T_c = 2.33(3)$ K and a high upper critical field. Transverse-field $\mu$SR measurements reveal an s-wave superconducting gap close to the BCS value, while zero-field $\mu$SR suggests preserved time-reversal symmetry. These results establish Cr-V-Ti-Nb-Ta as a promising platform for exploring the interplay between disorder, magnetism and superconductivity in high entropy alloys.

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Sonika Jangid, Rhea Stewart, Adrian D. Hillier, R. P. Singh. 2026-08-21. Superconducting ground state study of Cr-based equiatomic high-entropy alloy through $\mu\text{SR}$. https://arxiv.org/abs/2608.21273

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