Altermagnetic variants in thin films of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mi mathvariant="normal">M</mml:mi> <mml:msub> <mml:mi mathvariant="normal">n</mml:mi> <mml:mn>5</mml:mn> </mml:msub> <mml:mi mathvariant="normal">S</mml:mi> <mml:msub> <mml:mi mathvariant="normal">i</mml:mi> <mml:mn>3</mml:mn> </mml:msub> </mml:mrow> </mml:math>
Javier Rial, Miina Leiviskä, Gregor Skobjin, Antonín Baďura, Gilles Gaudin, F. Disdier, Richard Schlitz, Ismaïla Kounta, Sebastian Beckert, Dominik Kriegner, Andy Thomas, Eva Schmoranzerová, Libor Šmejkal, Jairo Sinova, T. Jungwirth, Lisa Michez, Helena Reichlová, Sebastian T. B. Goennenwein, Olena Gomonay, V. Baltz
Abstract
The altermagnet candidate $\mathrm{M}{\mathrm{n}}_{5}\mathrm{S}{\mathrm{i}}_{3}$ has attracted wide attention in the context of nonrelativistic spin physics, due to its composition of light elements. In this study, we demonstrate a hallmark of altermagnetism in $\mathrm{M}{\mathrm{n}}_{5}\mathrm{S}{\mathrm{i}}_{3}$ thin films, namely the three options, or variants, for the checkerboard distribution of the magnetic Mn atoms. The magnetic symmetries were altered by field-rotation of the N\'eel vector along relevant crystal directions, resulting in anomalous Hall effect anisotropy. The experimental results in nanoscale devices were corroborated by a theoretical model involving atomic site dependent anisotropy and bulk Dzyaloshinskii-Moriya interaction for a single variant. These findings elevate $\mathrm{M}{\mathrm{n}}_{5}\mathrm{S}{\mathrm{i}}_{3}$ from a candidate to a proven altermagnet.