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arXiv · 2102.11388

Higher-order topological phases in tunable $C_3$-symmetric photonic crystals

Hai-Xiao Wang·Li Liang·Bin Jiang·Junhui Hu·Xiancong Lu·Jian-Hua Jiang
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Abstract

We demonstrate that multiple higher-order topological transitions can be triggered via the continuous change of the geometry in kagome photonic crystals composed of three dielectric rods. By tuning a single geometry parameter, the photonic corner and edge states emerge or disappear with the higher-order topological transitions. Two distinct higher-order topological insulator phases and a normal insulator phase are revealed. Their topological indices are obtained from symmetry representations. A photonic analog of fractional corner charge is introduced to distinguish the two higher-order topological insulator phases. Our predictions can be readily realized and verified in configurable dielectric photonic crystals.

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Hai-Xiao Wang, Li Liang, Bin Jiang, Junhui Hu, Xiancong Lu, Jian-Hua Jiang. 2021-02-22. Higher-order topological phases in tunable $C_3$-symmetric photonic crystals. https://doi.org/10.1364/prj.433188

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