Spin-orbit coupling induced degeneracy in the anisotropic unconventional superconductor UTe.sub.2./sub.

0521301 - FZÚ 2020 RIV US eng J - Journal Article
Shick, Alexander - Pickett, W. E.
Spin-orbit coupling induced degeneracy in the anisotropic unconventional superconductor UTe₂.
Physical Review B. Roč. 100, č. 13 (2019), s. 1-9, č. článku 134502. ISSN 2469-9950. E-ISSN 2469-9969
R&D Projects: GA MŠMT(CZ) EF16_019/0000760; GA ČR GA18-02344S
Grant - others:OP VVV - SOLID21(XE) CZ.02.1.01/0.0/0.0/16_019/0000760
Institutional support: RVO:68378271
Keywords : fermi-surface * polarization
OECD category: Condensed matter physics (including formerly solid state physics, supercond.)
Impact factor: 3.575, year: 2019
Method of publishing: Limited access
https://doi.org/10.1103/physrevb.100.134502

The orthorhombic uranium dichalcogenide UTe2 displays superconductivity below 1.7 K, with the anomalous feature of retaining 50% of normal state (ungapped) carriers, according to heat capacity data from two groups. Incoherent transport that crosses over from above 50 K toward a low-temperature, Kondo lattice Fermi liquid regime indicates strong magnetic fluctuations and the need to include correlation effects in theoretical modeling. We report density functional theory plus Hubbard U (DFT+U) results for UTe2 to provide a platform for modeling its unusual behavior, focusing on ferromagnetic (FM, time-reversal breaking) long-range correlations along the (a) over cap axis as established by magnetization measurements and confirmed by our calculations. States near the Fermi level are dominated by the j = 5/2 configuration, with the j(z) = +/- 1/2 sectors being effectively degenerate and half-filled. Unlike the small-gap insulating nonmagnetic electronic spectrum, the FM Fermi surfaces are large (strongly metallic) and display low-dimensional features, reminiscent of the FM superconductor UGe2.
Permanent Link: http://hdl.handle.net/11104/0305930