Microscopic Identification of the Spin-Triplet Superconducting State of UBe 13

From a very detailed NMR study of UBe 13 , researchers could reconcile the results of macroscopic measurements pointing to a fully gapped superconducting state, with those of their microscopic probe. But they could also go much further, and identify precisely, thanks to Knight shift anisotropy measurements, the intricate symmetry of the spin-triplet superconducting order parameter in this system. These result on the oldest discovered uranium-based heavy fermion superconductor, could be a strong source of inspiration for UTe 2 , today’s star of the field, which still resist a consensus on the exact state of its superconducting phases.