Probing p-wave superconductivity in UTe2 via point-contact junctions
Hyeok Yoon, Yun Suk Eo, Ji Hun Park, Jarryd A. Horn, Ryan G. Dorman, Shanta Saha, Ian Hayes, Ichiro Takeuchi, P. M. R. Brydon, Johnpierre Paglione
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 dominant p y -wave gap function with amplitude 0.26 ± 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 .