Abstract
Spin-triplet superconductors are of extensive current interest because they can host topological state and Majorana fermions important for quantum computation. The uranium-based heavy-fermion superconductor UTe2 has been argued as a spin-triplet superconductor similar to UGe2, URhGe, and UCoGe, where the superconducting phase is near (or coexists with) a ferromagnetic (FM) instability and spin-triplet electron pairing is driven by FM spin fluctuations. Here we use neutron scattering to show that, although UTe2 exhibits no static magnetic order down to 0.3 K, its magnetism in the [0,K,L] plane is dominated by incommensurate spin fluctuations near an antiferromagnetic ordering wave vector and extends to at least 2.6 meV. We are able to understand the dominant incommensurate spin fluctuations of UTe2 in terms of its electronic structure calculated using a combined density-functional and dynamic mean-field theory.
| Original language | English |
|---|---|
| Article number | 237003 |
| Journal | Physical Review Letters |
| Volume | 125 |
| Issue number | 23 |
| DOIs | |
| State | Published - Dec 1 2020 |
Funding
The INS work at Rice is supported by the U.S. DOE, BES under Award No. DE-SC0012311 (P.\u2009D.). Part of the material characterization efforts at Rice is supported by the Robert A. Welch Foundation Grant No. C-1839 (P.\u2009D.). Research at UC San Diego was supported by the U.S. DOE, BES under Award No. DEFG02-04-ER46105 (single crystal growth) and U.S. NSF under Grant No. DMR-1810310 (characterization of physical properties). Work at Los Alamos was carried out under the auspices of the U.S. DOE National Nuclear Security Administration under Award No. 89233218CNA000001 and was supported by the LANL LDRD Program. The theory work at Rice has been supported by the U.S. DOE, BES under Award No. DE-SC0018197 and the Robert A. Welch Foundation Grant No. C-1411. A portion of this research used resources at the Spallation Neutron Source, a DOE Office of Science User Facility operated by ORNL.