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arXiv · 2505.13415

Optical signatures of bulk g-wave altermagnetism in MnTe

Luca Haag·Marius Weber·Kai Leckron·Libor Šmejkal·Jairo Sinova·Hans Christian Schneider
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Abstract

For planar d-wave altermagnets, it has been shown that a spin polarization can be induced in a controlled fashion by ultrashort-pulse excitation, even though the material is magnetically compensated. Here, we theoretically analyze the response of the prototypical bulk $g$-wave altermagnet $α$-MnTe to linearly polarized ultrashort pulses. We demonstrate how the electronic spin response in $α$-MnTe exhibits different symmetry characteristics by calculating the excited electron distributions based on ab initio band structure data. These characteristics depend not only on the nodal planes of the bulk g-wave altermagnet, but also on the excitation pulse. We present a simple procedure to analyze the excited-state characteristics via two-dimensional cuts through the three-dimensional Brillouin zone, which can be used as guidance to present-day magneto-optical techniques.

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Luca Haag, Marius Weber, Kai Leckron, Libor Šmejkal, Jairo Sinova, Hans Christian Schneider. 2026-06-25. Optical signatures of bulk g-wave altermagnetism in MnTe. https://doi.org/10.1103/ypfs-fy39

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