Speaker
Description
At a fundamental level, the altermagnetic phase manifests as collinear magnetism characterized by zero net magnetization, highlighting a distinct spin symmetry that emerges from the decoupling of spin and crystal space symmetries. MnTe exemplifies such a material, and Spin- and Angle-Resolved Photoemision Spectroscopy (SARPES) has proven to be an effective method for investigating its altermagnetic electronic structure. Recent findings of spin polarized band structures, coupled with a zero net magnetization in this extensively studied semiconductor, have validated the presence of this unique magnetic order [1]. Further comprehensive ARPES investigations suggest that MnTe-and potentially other collinear altermagnets as well-exhibit an unconventional photoresponse to polarized light that cannot be accounted for by traditional photoemission selection rules. We demonstrate that this phenomenon pertains to both surface-derived bands observed in UV-ARPES and bulk MnTe bands detected in the soft-X regime.
References
[1] J. Krempaský et al., “Altermagnetic lifting of Kramers spin degeneracy,” Nature, vol. 626, no. 7999. Springer Science and Business Media LLC, pp. 517–522, Feb. 14, 2024. https://doi.org/10.1038/s41586-023-06907-7.
