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arXiv · 2501.17380

Chiral Altermagnon in MnTe

Daniel Jost·Resham B. Regmi·Eder G. Lomeli·Samuel Sahel-Schackis·Monika Scheufele·Marcel Neuhaus·Rachel Nickel·Flora Yakhou·Kurt Kummer·Nicholas Brookes·Lingjia Shen·Georgi L. Dakovski·Nirmal J. Ghimire·Stephan Geprägs·Matthias F. Kling
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Abstract

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.

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Daniel Jost, Resham B. Regmi, Eder G. Lomeli, Samuel Sahel-Schackis, Monika Scheufele, Marcel Neuhaus, Rachel Nickel, Flora Yakhou, Kurt Kummer, Nicholas Brookes, Lingjia Shen, Georgi L. Dakovski, Nirmal J. Ghimire, Stephan Geprägs, Matthias F. Kling. 2025-01-29. Chiral Altermagnon in MnTe. https://arxiv.org/abs/2501.17380

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