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arXiv · 2502.14861

Stacking-dependent topological electronic structures in honeycomb-kagome heterolayers

Chan Bin Bark·Hanbyul Kim·Seik Pak·Hong-Guk Min·Sungkyun Ahn·Youngkuk Kim·Moon Jip Park
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Abstract

Heterostructures of stacked two-dimensional lattices have shown great promise for engineering novel material properties. As an archetypal example of such a system, the hexagon-shared honeycomb-kagome lattice has been experimentally synthesized in various material platforms. In this work, we explore three rotationally symmetric variants of the honeycomb-kagome lattice: the hexagonal, triagonal, and biaxial phases. While the triagonal and biaxial phases exhibit trivial insulating and Dirac semimetal band structures, respectively, the hexagonal phase hosts a higher-order topological phase driven by band inversion near the $\Gamma$-point. This highlights a key distinction from the conventional band inversions at the $K$-point observed in hexagonal homobilayer systems. Furthermore, we demonstrate how the distinct topological properties of these phases result in network band structures within moir\'e heterostructures formed by twisted or lattice-mismatched HK systems. These network band structures can be experimentally observed through extrinsic twisting or intrinsic lattice mismatching between the honeycomb and kagome systems.

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Chan Bin Bark, Hanbyul Kim, Seik Pak, Hong-Guk Min, Sungkyun Ahn, Youngkuk Kim, Moon Jip Park. 2025-02-20. Stacking-dependent topological electronic structures in honeycomb-kagome heterolayers. https://arxiv.org/abs/2502.14861

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