Altermagnetism has surfaced as a novel magnetic phase, bridging the properties of ferro- and anti-ferromagnetism. The momentum-dependent spin-splitting observed in these materials reflects their unique symmetry characteristics, which also establish the conditions for chiral magnons to emerge. Here we provide the first direct experimental evidence for a chiral magnon in the altermagnetic candidate MnTe revealed by circular-dichroism resonant inelastic X-ray scattering (CD-RIXS). This mode which we term chiral altermagnon exhibits a distinct momentum dependence of its spin polarization consistent with the proposed altermagnetic g−wave symmetry of MnTe. Our polarization-resolved results corroborate the existence of a new class of magnetic excitations, demonstrating how altermagnetic order shapes spin dynamics and paves the way for advances in spintronic and quantum technologies.
@article{arxiv.2501.17380,
title = {Chiral Altermagnon in MnTe},
author = {Daniel Jost and Resham B. Regmi and Eder G. Lomeli and Samuel Sahel-Schackis and Monika Scheufele and Marcel Neuhaus and Rachel Nickel and Flora Yakhou and Kurt Kummer and Nicholas Brookes and Lingjia Shen and Georgi L. Dakovski and Nirmal J. Ghimire and Stephan Geprägs and Matthias F. Kling},
journal= {arXiv preprint arXiv:2501.17380},
year = {2025}
}