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arXiv · 2606.02152

Stacking-Engineered Switchable Altermagnetism in Topological FeSe bilayer systems

Jie Li·Shifang Li·Mengyang Zhang·Pan Zhou·Jianxin Zhong·Ruqian Wu
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Abstract

Altermagnetism and topological insulators represent two of the most transformative frontiers in modern condensed matter physics, spintronics, and quantum information science. Bringing these two paradigms together opens a largely unexplored route toward fundamentally new quantum phenomena. Here, we predict a topological altermagnetic phase in bilayer tetragonal Fe-based superconductors and reveal it as a highly tunable platform for valley-polarized anomalous Hall physics. Based on first-principles calculations, we show that the characteristic spin-splitting and valley polarization can be effectively tuned via applied strain. Moreover, the resulting valley-polarized anomalous Hall conductivity can be manipulated by shifting the Fermi level. These findings reveal a powerful route for controlling altermagnetism in topological materials and identify a realistic material platform for its experimental realization and technological exploitation.

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Jie Li, Shifang Li, Mengyang Zhang, Pan Zhou, Jianxin Zhong, Ruqian Wu. 2026-06-01. Stacking-Engineered Switchable Altermagnetism in Topological FeSe bilayer systems. https://arxiv.org/abs/2606.02152

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