Multicomponent superconducting order parameter in UTe2

I M Hayes; D S Wei; T Metz; J Zhang; Y S Eo; S Ran; S R Saha; J Collini; N P Butch; D F Agterberg; A Kapitulnik; J Paglione

doi:10.1126/science.abb0272

Multicomponent superconducting order parameter in UTe₂

Science. 2021 Aug 13;373(6556):797-801. doi: 10.1126/science.abb0272. Epub 2021 Jul 15.

Authors

I M Hayes^#¹, D S Wei^#^{2

3

4}, T Metz^{5

1}, J Zhang^{1

5}, Y S Eo¹, S Ran^{4

1

2}, S R Saha^{1

2}, J Collini¹, N P Butch^{5

6

1

2}, D F Agterberg^{3

6}, A Kapitulnik^{7

4

8

9}, J Paglione^{10

1

2

11}

Affiliations

¹ Department of Physics, Quantum Materials Center, University of Maryland, College Park, MD 20742, USA.
² NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA.
³ Geballe Laboratory for Advanced Materials, Stanford University, Stanford, CA 94305, USA.
⁴ Department of Applied Physics, Stanford University, Stanford, CA 94305, USA.
⁵ State Key Laboratory of Surface Physics, Department of Physics, Fudan University, Shanghai 200433, China.
⁶ Department of Physics, University of Wisconsin-Milwaukee, Milwaukee, WI 53201, USA.
⁷ Geballe Laboratory for Advanced Materials, Stanford University, Stanford, CA 94305, USA. [email protected] [email protected].
⁸ Department of Physics, Stanford University, Stanford, CA 94305, USA.
⁹ Stanford Institute for Materials and Energy Sciences (SIMES), SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025, USA.
¹⁰ State Key Laboratory of Surface Physics, Department of Physics, Fudan University, Shanghai 200433, China. [email protected] [email protected].
¹¹ The Canadian Institute for Advanced Research, Toronto, Ontario, Canada.

^# Contributed equally.

PMID: 34385397
DOI: 10.1126/science.abb0272

Abstract

An unconventional superconducting state was recently discovered in uranium ditelluride (UTe₂), in which spin-triplet superconductivity emerges from the paramagnetic normal state of a heavy-fermion material. The coexistence of magnetic fluctuations and superconductivity, together with the crystal structure of this material, suggests that a distinctive set of symmetries, magnetic properties, and topology underlie the superconducting state. Here, we report observations of a nonzero polar Kerr effect and of two transitions in the specific heat upon entering the superconducting state, which together suggest that the superconductivity in UTe₂ is characterized by a two-component order parameter that breaks time-reversal symmetry. These data place constraints on the symmetries of the order parameter and inform the discussion on the presence of topological superconductivity in UTe₂.

Publication types

Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.