Current browse context:
cond-mat.str-el
Change to browse by:
References & Citations
Condensed Matter > Strongly Correlated Electrons
Title: Spin-orbit enabled unconventional Stoner magnetism
(Submitted on 2 Oct 2023 (v1), last revised 1 Mar 2024 (this version, v2))
Abstract: The Stoner instability remains a cornerstone for understanding metallic ferromagnets. This instability captures the interplay of Coulomb repulsion, Pauli exclusion, and two-fold fermionic spin degeneracy. In materials with spin-orbit coupling, this fermionic spin is generalized to a two-fold degenerate pseudospin which is typically believed to have symmetry properties as spin. Here we identify a distinct symmetry of this pseudospin that forbids it to couple to a Zeeman field. This `spinless' property is required to exist in five non-symmorphic space groups and has non-trivial implications for superconductivity and magnetism. With Coulomb repulsion, Fermi surfaces composed primarily of this spinless pseudospin feature give rise to Stoner instabilities into magnetic states that are qualitatively different than ferromagnets. These spinless-pseudospin ferromagnets break time-reversal symmetry, have a vanishing magnetization, are non-collinear, and exhibit altermagnetic-like energy band spin-splittings. In superconductors, for all pairing symmetries and field orientations, this spinless pseudospin extinguishes paramagnetic limiting. We discuss applications to superconducting UCoGe and magnetic NiS$_{2-x}$Se$_x$.
Submission history
From: Yue Yu [view email][v1] Mon, 2 Oct 2023 01:24:13 GMT (2654kb,D)
[v2] Fri, 1 Mar 2024 00:36:19 GMT (3209kb,D)
Link back to: arXiv, form interface, contact.