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arXiv · 2210.02749

Hinge States of Second-Order Topological Insulators as a Mach-Zehnder Interferometer

Adam Yanis Chaou·Piet W. Brouwer·Nicholas Sedlmayr
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Abstract

Three-dimensional higher-order topological insulators can have topologically protected chiral modes propagating on their hinges. Hinges with two co-propagating chiral modes can serve as a "beam splitter" between hinges with only a single chiral mode. Here we show how such a crystal, with Ohmic contacts attached to its hinges, can be used to realize a Mach-Zehnder interferometer. We present concrete calculations for a lattice model of a first-order topological insulator in a magnetic field, which, for a suitable choice of parameters, is an extrinsic second-order topological insulator with the required configuration of chiral hinge modes.

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Adam Yanis Chaou, Piet W. Brouwer, Nicholas Sedlmayr. 2022-10-06. Hinge States of Second-Order Topological Insulators as a Mach-Zehnder Interferometer. https://doi.org/10.1103/physrevb.107.035430

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