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arXiv · 2604.19929

Topological Edge States Emerging from Twisted Moir\'e Bands

Yasser Saleem·Paweł Potasz·Anna Dyrdał·Björn Trauzettel·Ewelina M. Hankiewicz
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Abstract

We study twisted bilayer WSe$_2$ within a continuum moir\'e model and introduce a method for treating finite geometries directly in the continuum framework, overcoming limitations associated with momentum-space formulations and Wannier obstructions. By projecting a confinement potential onto bulk moir\'e eigenstates, we obtain a real-space description of edge physics without lattice models. Applying this approach to nanoribbons, we demonstrate chiral edge modes consistent with bulk Chern numbers and reveal their moir\'e-scale character. In the magic-angle regime, these states are strongly localized, exhibit layer-polarized counter-propagating modes, and are electrically tunable via a displacement field, enabling control of localization, hybridization, and topological transitions. Our results establish a general framework for boundary physics in topological moir\'e materials.

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Yasser Saleem, Paweł Potasz, Anna Dyrdał, Björn Trauzettel, Ewelina M. Hankiewicz. 2026-04-21. Topological Edge States Emerging from Twisted Moir\'e Bands. https://arxiv.org/abs/2604.19929

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