Chiral-Split Magnon in Altermagnetic MnTe

TL;DR

This paper experimentally verifies chiral splitting in magnon bands of altermagnetic MnTe using inelastic neutron scattering, revealing symmetric-exchange origins and identifying $g$-wave magnetism, thus advancing understanding of altermagnetic excitations.

Contribution

It provides the first direct experimental evidence of chiral magnon splitting in altermagnets, specifically MnTe, and explains its symmetric-exchange origin.

Findings

Verified chiral splitting in MnTe magnon bands

Identified symmetric-exchange as the origin of degeneracy lifting

Discovered $g$-wave magnetism in MnTe

Abstract

Altermagnetism is a newly discovered magnetic class named after the alternating spin polarizations in both real and reciprocal spaces. Like the spin-splitting of electronic bands, the magnon bands in altermagnets are predicted to exhibit alternating chiral splitting. In this work, by performing inelastic neutron scattering on $\alpha$-MnTe, we directly verified the chiral splitting in altermagnetic magnon dispersions. The lifted degeneracy of chirality is further explained by a symmetric-exchange origin. In addition, the $g$-wave magnetism was identified in MnTe.