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arXiv · 2112.10205

Bulk-edge correspondence and trapping at a non-Hermitian topological interface

Stefano Longhi
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Abstract

In Hermitian systems, according to the bulk-edge correspondence interfacing two topological optical media with different bulk topological numbers implies the existence of edge states, which can trap light at the interface. However, such a general scenario can be violated when dealing with non-Hermitian systems. Here we show that interfacing two semi-infinite Hatano-Nelson chains with different bulk topological numbers can result in the existence of infinitely many edge (interface) states, however light waves cannot be rather generally trapped at the interface.

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Stefano Longhi. 2021-12-19. Bulk-edge correspondence and trapping at a non-Hermitian topological interface. https://doi.org/10.1364/ol.445437

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