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arXiv · 2106.06223

Field-Tunable One-Sided Higher-Order Topological Hinge States in Dirac Semimetals

Rui Chen·Tianyu Liu·C. M. Wang·Hai-Zhou Lu·X. C. Xie
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Abstract

Recently, higher-order topological matter and 3D quantum Hall effects have attracted great attention. The Fermi-arc mechanism of the 3D quantum Hall effect proposed in Weyl semimetals is characterized by the one-sided hinge states, which do not exist in all the previous quantum Hall systems and more importantly pose a realistic example of the higher-order topological matter. The experimental effort so far is in the Dirac semimetal Cd$_3$As$_2$, where however time-reversal symmetry leads to hinge states on both sides of the top/bottom surfaces, instead of the aspired one-sided hinge states. We propose that under a tilted magnetic field, the hinge states in Cd$_3$As$_2$-like Dirac semimetals can be one-sided, highly tunable by field direction and Fermi energy, and robust against weak disorder. Furthermore, we propose a scanning tunneling Hall measurement to detect the one-sided hinge states. Our results will be insightful for exploring not only the quantum Hall effects beyond two dimensions, but also other higher-order topological insulators in the future.

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Rui Chen, Tianyu Liu, C. M. Wang, Hai-Zhou Lu, X. C. Xie. 2021-08-04. Field-Tunable One-Sided Higher-Order Topological Hinge States in Dirac Semimetals. https://doi.org/10.1103/physrevlett.127.066801

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