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arXiv · 1807.01277

Inversion-symmetry protected chiral hinge states in stacks of doped quantum Hall layers

Sander H. Kooi·Guido van Miert·Carmine Ortix
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Abstract

We prove the existence of higher-order topological insulators with protected chiral hinge modes in quasi-two-dimensional systems made out of coupled layers stacked in an inversion-symmetric manner. In particular, we show that an external magnetic field drives a stack of alternating p- and n-doped buckled honeycomb layers into a higher-order topological phase, characterized by a non-trivial three-dimensional ${\mathbb Z}_2$ invariant. We identify silicene multilayers as a potential material platform for the experimental detection of this novel topological insulating phase.

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Sander H. Kooi, Guido van Miert, Carmine Ortix. 2018-07-03. Inversion-symmetry protected chiral hinge states in stacks of doped quantum Hall layers. https://doi.org/10.1103/physrevb.98.245102

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