Exploration of the High Field Properties of Heavy Fermion UTe₂

Unconventional superconductivity in uranium ditelluride has elicited a great deal of interest since first reported in 2019. The upper critical field exceeds the Pauli limit in all directions, with superconductivity persisting to up to 34.5 T when H || b, the magnetic hard axis. Above 40 T, when H is tilted approx. 30^o in the bc plane, a high field superconducting phase develops, which itself persists to at least 65 T. These remarkable properties indicate UTe₂ to be a spin triplet superconductor, wherein one or all of the superconducting phases exhibit a topologically non-trivial wavefunction. Moreover, recent STM investigations into the low field superconducting phase evidenced chiral edge states in the superconducting gap, suggesting UTe₂ as a candidate platform for the realization and manipulation of elusive Majorana edge modes. In this talk, I will discuss some of the high field properties of superconducting UTe₂, focusing primarily on resistivity measurements at various angular offsets from b.