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arXiv · 2003.11271

Multiple-gap response of type-I noncentrosymmetric BeAu superconductor

Rustem Khasanov·Ritu Gupta·Debarchan Das·Alfred Amon·Andreas Leithe-Jasper·Eteri Svanidze
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Abstract

Precise measurements of the thermodynamic critical field ($B_{\rm c}$) in type-I noncentrosymmetric superconductor BeAu were performed by means of the muon-spin rotation/relaxation technique. The temperature evolution of $B_{\rm c}$ can not be described within the single gap scenario and it requires the presence of at least two different types of the superconducting order parameters. The self-consistent two-gap approach, adapted for analysis of $B_{\rm c}(T)$ behavior, suggests the presence of two superconducing energy gaps with the gap to $T_{\rm c}$ ratios $2\Delta/k_{\rm B}T_{\rm c}\simeq4.52$ and $\simeq2.37$ for the big and the small gap, respectively. This implies that the superconductivity in BeAu is unconventional and that the supercarrier pairing occurs at various energy bands.

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Rustem Khasanov, Ritu Gupta, Debarchan Das, Alfred Amon, Andreas Leithe-Jasper, Eteri Svanidze. 2020-03-25. Multiple-gap response of type-I noncentrosymmetric BeAu superconductor. https://doi.org/10.1103/physrevresearch.2.023142

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