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arXiv · 2510.15357

Altermagnetism induced surface Chern insulator

Xuance Jiang·Sayed Ali Akbar Ghorashi·Deyu Lu·Jennifer Cano
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Abstract

We propose a new pathway to the quantized anomalous Hall effect (QAHE) by coupling an altermagnet to a topological crystalline insulator (TCI). The former gaps the topological surface states of the TCI, thereby realizing the QAHE in a robust and switchable platform with near- vanishing magnetization. We demonstrate the feasibility of this approach by studying a slab of the TCI SnTe coupled to an altermagnetic RuO2 layer. Our first-principles calculations reveal that the d-wave altermagnetism in RuO2 induces a 7 meV gap to the Dirac surface states on the (110) surface of SnTe, producing a finite anomalous Hall effect. Our approach generalizes to broader classes of altermagnetic materials and TCIs, thereby providing a family of topological altermagnetic heterostructures with small or vanishing magnetization that support nontrivial Chern numbers. Our results highlight a promising new topological platform with great tunability and applications to spintronics.

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Xuance Jiang, Sayed Ali Akbar Ghorashi, Deyu Lu, Jennifer Cano. 2025-10-17. Altermagnetism induced surface Chern insulator. https://arxiv.org/abs/2510.15357

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