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arXiv · 2302.07752

Effects of the Vertices on the Topological Bound States in a Quasicrystalline Topological Insulator

Simone Traverso·Niccolò Traverso Ziani·Maura Sassetti
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Abstract

The experimental realization of twisted bilayer graphene strongly pushed the inspection of bilayer systems. In this context, it was recently shown that a two layer Haldane model with a thirty degree rotation angle between the layers represents a higher order topological insulator, with zero-dimensional states isolated in energy and localized at the physical vertices of the nanostructure. We show, within a numerical tight binding approach, that the energy of the zero dimensional states strongly depends on the geometrical structure of the vertices. In the most extreme cases, once a specific band gap is considered, these bound states can even disappear just by changing the vertex structure.

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Simone Traverso, Niccolò Traverso Ziani, Maura Sassetti. 2023-02-15. Effects of the Vertices on the Topological Bound States in a Quasicrystalline Topological Insulator. https://doi.org/10.3390/sym14081736

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