Probing $p$-wave superconductivity in UTe$_2$ via point-contact junctions

Hyeok Yoon; Yun Suk Eo; Jihun Park; Jarryd A. Horn; Ryan G. Dorman; Shanta R. Saha; Ian M. Hayes; Ichiro Takeuchi; Philip M. R. Brydon; Johnpierre Paglione

arXiv · 2403.00933

Probing $p$-wave superconductivity in UTe$_2$ via point-contact junctions

Hyeok Yoon·Yun Suk Eo·Jihun Park·Jarryd A. Horn·Ryan G. Dorman·Shanta R. Saha·Ian M. Hayes·Ichiro Takeuchi·Philip M. R. Brydon·Johnpierre Paglione

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Abstract

Uranium ditelluride (UTe$_2$) is the strongest contender to date for a $p$-wave superconductor in bulk form. Here we perform a spectroscopic study of the ambient pressure superconducting phase of UTe$_2$, measuring conductance through point-contact junctions formed by metallic contacts on different crystalline facets down to 250 mK and up to 18 T. Fitting a range of qualitatively varying spectra with a Blonder-Tinkham-Klapwijk(BTK) model for $p$-wave pairing, we can extract gap amplitude and interface barrier strength for each junction. We find good agreement with the data for a $p_y$ -wave gap function with amplitude in 0.26 $\pm$ 0.06 meV. Our work provides spectroscopic evidence for a gap structure consistent with the proposed spin-triplet pairing in the superconducting state of UTe$_2$.

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Hyeok Yoon, Yun Suk Eo, Jihun Park, Jarryd A. Horn, Ryan G. Dorman, Shanta R. Saha, Ian M. Hayes, Ichiro Takeuchi, Philip M. R. Brydon, Johnpierre Paglione. 2024-03-01. Probing $p$-wave superconductivity in UTe$_2$ via point-contact junctions. https://arxiv.org/abs/2403.00933

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