TY - JOUR
T1 - Field-Induced Tuning of the Pairing State in a Superconductor
AU - Rosuel, A.
AU - Marcenat, C.
AU - Knebel, G.
AU - Klein, T.
AU - Pourret, A.
AU - Marquardt, N.
AU - Niu, Q.
AU - Rousseau, S.
AU - Demuer, A.
AU - Seyfarth, G.
AU - Lapertot, G.
AU - Aoki, D.
AU - Braithwaite, D.
AU - Flouquet, J.
AU - Brison, J. P.
N1 - Publisher Copyright:
© 2023 authors. Published by the American Physical Society. Published by the American Physical Society under the terms of the "https://creativecommons.org/licenses/by/4.0/"Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.
PY - 2023/1/1
Y1 - 2023/1/1
N2 - The recently discovered superconductor UTe2, with a superconducting transition temperature Tc between 1.5 and 2 K, is attracting much attention due to strong suspicion of spin-triplet and topological superconductivity. Its properties under magnetic field are also remarkable, with field-reinforced (H∥b) and field-induced [H in the (b,c) plane] superconducting phases. Here, we report the first complete thermodynamic determination of the phase diagram for fields applied along the three crystallographic directions. For field along the easy a axis, we uncover a strong negative curvature of the upper critical field very close to Tc, revealing a strong suppression of the pairing strength at low magnetic fields. By contrast, measurements performed up to 36 T along the hard magnetization b axis confirm a bulk field-reinforced superconducting phase. Most of all, they also reveal the existence of a phase transition line within the superconducting phase. Drastic differences occur between the low-field and high-field phases pointing to different pairing mechanisms. Detailed analysis suggests a possible transition between a low-field spin-triplet to high-field spin-singlet state, a unique case among superconductors.
AB - The recently discovered superconductor UTe2, with a superconducting transition temperature Tc between 1.5 and 2 K, is attracting much attention due to strong suspicion of spin-triplet and topological superconductivity. Its properties under magnetic field are also remarkable, with field-reinforced (H∥b) and field-induced [H in the (b,c) plane] superconducting phases. Here, we report the first complete thermodynamic determination of the phase diagram for fields applied along the three crystallographic directions. For field along the easy a axis, we uncover a strong negative curvature of the upper critical field very close to Tc, revealing a strong suppression of the pairing strength at low magnetic fields. By contrast, measurements performed up to 36 T along the hard magnetization b axis confirm a bulk field-reinforced superconducting phase. Most of all, they also reveal the existence of a phase transition line within the superconducting phase. Drastic differences occur between the low-field and high-field phases pointing to different pairing mechanisms. Detailed analysis suggests a possible transition between a low-field spin-triplet to high-field spin-singlet state, a unique case among superconductors.
UR - https://www.scopus.com/pages/publications/85149644943
U2 - 10.1103/PhysRevX.13.011022
DO - 10.1103/PhysRevX.13.011022
M3 - Article
AN - SCOPUS:85149644943
SN - 2160-3308
VL - 13
JO - Physical Review X
JF - Physical Review X
IS - 1
M1 - 011022
ER -