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arXiv · 2002.09374

Topological chiral interface states beyond insulators

Lavi K. Upreti·P. Delplace
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Abstract

We show how to engineer a chiral spectral flow of interface states in a gapless system. Although the bulk bands touch -- thus making the topological indices of the bands ill-defined -- this spectral flow has a topological origin that makes it robust even when it coexists with the bulk bands. This phenomenon is illustrated with an adiabatically modulated photonic quantum walk.

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Lavi K. Upreti, P. Delplace. 2020-02-21. Topological chiral interface states beyond insulators. https://doi.org/10.1103/physreva.102.023520

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