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arXiv · 2007.05900

Exceptional points in a topological photonic system

Junhua Dong·Chang-Yin Ji·Qingmei Hu·Bingsuo Zou·Yongyou Zhang
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Abstract

Exceptional points as branch singularities describe peculiar degeneracies of non-Hermitian systems that do not obey energy conservation. This work shows that exceptional points can emerge in a topological photonic system, for example, the topological photonic waveguide coupled with two degenerate counter-propagation topological whispering gallery modes. Such a photonic architecture is designed by crystal-symmetry-protected topological photonic insulators based on air rods in conventional dielectric materials. The relevant exceptional point reveals the breaking of the parity-time symmetry, reflected by the change of the transmission-dip number in the optical transmission spectra of the system. Achieving exceptional points in topological photonic systems possibly opens a new avenue toward robust optical devices with exceptional-point-based unique properties and functionalities.

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Junhua Dong, Chang-Yin Ji, Qingmei Hu, Bingsuo Zou, Yongyou Zhang. 2020-07-12. Exceptional points in a topological photonic system. https://arxiv.org/abs/2007.05900

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