Uranium Ditelluride and the Limits of Superconductivity in Extreme Magnetic Fields

Though applied magnetic fields are anathema to conventional BCS superconductors, field stabilized superconductivity has been seen in unconventional superconductors such as URhGe and UCoGe. Generally, models of high-field superconductivity, such as the Jaccarino-Peter effect, pre-suppose the presence of a zero-field parent phase. In UTe₂, re-entrant superconductivity above 35 T has been reported to have a similar transition temperature and thus energy scale to the H = 0 field phase, and thus a presumptively similar sensitivity to impurity scattering. However, we have recently reported high field stabilized superconductivity in single crystals of UTe₂ which lack low-and-intermediate field parent phases. This evidence that high field superconductivity in UTe₂ is exceptionally robust challenges previously proposed theoretical explanations, and dramatically limits possible mechanisms for the stabilization of the high field phase. In this talk, I will present our recent finding of orphan superconductivity in “non-superconducting” UTe₂, and discuss its implications on the theoretical landscape.

Co-Authors:

*Corey E. Frank,^1,2 Sylvia K, Lewin,^1,2 Gicela Saucedo Salas,^2,1 Peter Czajka,^1,2 Thomas Halloran,^1,2 Ian Hayes,² Hyeok Yoon,² Tristin Metz,² Johnpierre Paglione,² John Singleton,³ *Nicholas P. Butch^1,2

1. 1. NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD, USA
   
   2. Maryland Quantum Materials Center, Department of Physics, University of Maryland, College Park, MD, USA
   
   3. National High Magnetic Field Laboratory, Los Alamos National Laboratory, Los Alamos, NM, USA