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arXiv · 2307.04334

Quasicrystalline second-order topological semimetals

Rui Chen·Bin Zhou·Dong-Hui Xu
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Abstract

Three-dimensional higher-order topological semimetals in crystalline systems exhibit higher-order Fermi arcs on one-dimensional hinges, challenging the conventional bulk-boundary correspondence. However, the existence of higher-order Fermi arc states in aperiodic quasicrystalline systems remains uncertain. In this work, we present the emergence of three-dimensional quasicrystalline second-order topological semimetal phases by vertically stacking two-dimensional quasicrystalline second-order topological insulators. These quasicrystalline topological semimetal phases are protected by rotational symmetries forbidden in crystals, and are characterized by topological hinge Fermi arcs connecting fourfold degenerate Dirac-like points in the spectrum. Our findings reveal an intriguing class of higher-order topological phases in quasicrystalline systems, shedding light on their unique properties.

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Rui Chen, Bin Zhou, Dong-Hui Xu. 2023-07-10. Quasicrystalline second-order topological semimetals. https://doi.org/10.1103/physrevb.108.195306

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