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arXiv · 2608.07099

Topological surface altermagnets in SSH-stacked magnetic layers

Rui Chen·Bin Zhou·Dong-Hui Xu
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Abstract

Surface altermagnetism opens new avenues in spintronics by unlocking altermagnetic spin-splitting at the boundaries of conventional antiferromagnets, bypassing the strict symmetry requirements of bulk altermagnets. In this work, we propose creating topological surface altermagnet by stacking magnetic layers in a Su-Schrieffer-Heeger pattern. We show that while the bulk of the system is a standard antiferromagnet with degenerate bands protected by $PT$ symmetry, breaking the local symmetry at the boundary gives rise to a topologically protected surface altermagnetic state residing within the topological gap. Furthermore, we propose that this effect can be experimentally detected by applying a perpendicular electric field. Besides, this approach can be readily generalized to surface altermagnetism of different types. Our work establishes topological boundaries as a natural platform for surface altermagnetism, offering a distinct route for realizing and manipulating topological surface altermagnets.

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Rui Chen, Bin Zhou, Dong-Hui Xu. 2026-08-07. Topological surface altermagnets in SSH-stacked magnetic layers. https://arxiv.org/abs/2608.07099

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