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arXiv · 2605.06551

Twisted Kagome Bilayers: High-Order Van Hove Singularities, Sublattice Interference, Magic Angles, and Possible Topology

David T. S. Perkins·Joseph J. Betouras
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Abstract

We develop a low-energy continuum model to describe the moir\'{e} physics of heterostructures, which is a generalization of the celebrated Bistritzer-MacDonald (BM) method [R. Bistritzer and A. H. MacDonald, Proc. Natl. Acad. Sci. U.S.A. 108, 12233 (2011)]. We take as an example the moir\'{e} physics of electrons in twisted bilayer kagome metals near 1/3 filling where monolayer Dirac cones lie. We demonstrate the emergence of magic angles where significant local band flattening occurs as a high-order Van Hove singularity appears and find a momentum-dependent anti-unitary particle-hole symmetry potentially enabling stable topology. We, furthermore, show that while sublattice interference effects are present, their role is not as prominent as in monolayer kagome.

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David T. S. Perkins, Joseph J. Betouras. 2026-05-07. Twisted Kagome Bilayers: High-Order Van Hove Singularities, Sublattice Interference, Magic Angles, and Possible Topology. https://arxiv.org/abs/2605.06551

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