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arXiv · 1911.10547

Quasicrystalline Chern Insulators

Ai-Lei He·Lu-Rong Ding·Yuan Zhou·Yi-Fei Wang·Chang-De Gong
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Abstract

Chern insulator or quantum anomalous Hall state is a topological state with integer Hall conductivity but in absence of Landau level. It had been well established on various two-dimensional lattices with periodic structure. Here, we report similar Chern insulators can also be realized on the quasicrystal with $5$-fold rotational symmetry. Providing the staggered flux through plaquettes, we propose two types of quasicrystalline Chern insulators. Their topological characterizations are well identified by the robustness of edge states, non-zero real-space Chern number, and quantized conductance. We further find the failure of integer conductivity but with quantized Chern number at some special energies. Our study therefore provide a new opportunity to searching topological materials in aperiodic system.

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Ai-Lei He, Lu-Rong Ding, Yuan Zhou, Yi-Fei Wang, Chang-De Gong. 2019-11-24. Quasicrystalline Chern Insulators. https://doi.org/10.1103/physrevb.100.214109

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