Unconventional relativistic spin polarization of electronic bands in an altermagnet
Abstract
Altermagnetism is a recently identified phase with a d, g or i-wave spin symmetry of magnetic ordering. Its discovery opens new research fronts at intersections of magnetism and spintronics with fields ranging from superconductivity to topological and relativistic quantum physics. Here we demonstrate an unconventional relativistic spin polarization in an altermagnet by spin and angle resolved photoemission spectroscopy of electronic bands in single-domain MnTe. The relativistic spin-orbit coupling origin is revealed by observing that the alternating momentum-dependent spin polarization is orthogonal to the magnetic-ordering vector. The collinearity, even-parity and time-reversal-odd nature of the demonstrated relativistic spin polarization in the altermagnet is unparalleled in conventional forms of the relativistic spin polarization. Our experimental results and methodology are supported by non-relativistic spin-symmetry and relativistic magnetic-symmetry analyses, and microscopic ab initio ground-state and photoemission theory.
Keywords
Cite
@article{arxiv.2511.01690,
title = {Unconventional relativistic spin polarization of electronic bands in an altermagnet},
author = {A. Dal Din and D. A. Usanov and L. Šmejkal and S. W. D'Souza and F. Guo and O. J. Amin and E. M. Dawa and R. P. Campion and K. W. Edmonds and B. Kiraly and A. W. Rushforth and C. Polley and M. Leandersson and E. Golias and Y. Niu and S. Telkamp and F. Krizek and A. Birk Hellenes and J. Priessnitz and W. H. Campos and J. Krempaský and J. Minár and T. Jungwirth and J. H. Dil and P. Wadley},
journal= {arXiv preprint arXiv:2511.01690},
year = {2025}
}
Comments
14 pages, 4 figures