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arXiv · 2506.12449

Unconventional superconductivity in a non-centrosymmetric ${\alpha}$-Mn alloy NbTaOs$_{2}$

R. K. Kushwaha·Arushi·S. Jangid·P. K. Meena·R. Stewart·A. D. Hillier·R. P. Singh
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Abstract

Non-centrosymmetric superconductors have emerged as a fascinating avenue for exploring unconventional superconductivity. Their broken inversion and time-reversal symmetries make them prime candidates for realizing the intrinsic superconducting diode effect (SDE). In this work, we synthesize the ternary non-centrosymmetric $\alpha$-Mn alloy NbTaOs$_{2}$ and conduct a comprehensive investigation of its superconducting properties through resistivity, magnetization, specific heat and muon spin rotation/relaxation ($\mu$SR) techniques. Our transverse field-$\mu$SR and specific heat results provide evidence of a moderately coupled, fully-gaped superconducting state. Zero field-$\mu$SR measurements reveal a subtle increase in the relaxation rate below the transition temperature, suggesting time reversal symmetry breaking in the superconducting ground state of NbTaOs$_{2}$.

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R. K. Kushwaha, Arushi, S. Jangid, P. K. Meena, R. Stewart, A. D. Hillier, R. P. Singh. 2025-06-14. Unconventional superconductivity in a non-centrosymmetric ${\alpha}$-Mn alloy NbTaOs$_{2}$. https://arxiv.org/abs/2506.12449

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