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Updated: Aug 9, 2025
12:18
Microwave Photonics Systems Based on Whispering-gallery-mode Resonators
Published on: August 5, 2013
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Topological Unidirectional Guided Resonances Emerged from Interband Coupling
Xuefan Yin1, Takuya Inoue1, Chao Peng2,3
1Department of Electronic Science and Engineering, Kyoto University, Kyoto-Daigaku-Katsura, Nishikyo-ku, Kyoto 615-8510, Japan.
Physical Review Letters
|February 17, 2023
Summary
Researchers discovered a new way to control light using unidirectional guided resonances (UGRs) by breaking symmetry. This breakthrough offers novel methods for advanced light manipulation in photonic devices.
Area of Science:
- Photonics
- Optical Physics
- Materials Science
Background:
- Unidirectional guided resonances (UGRs) are specialized optical modes in photonic crystal slabs.
- UGRs enable one-sided radiation without requiring mirrors, simplifying device design.
Purpose of the Study:
- To introduce a novel mechanism for realizing UGRs.
- To explore the topological properties and control of UGRs.
Main Methods:
- Theoretical investigation of interband coupling effects.
- Analysis of symmetry breaking in photonic crystal slabs.
- Examination of phase singularities and topological indices in far-field radiation.
Main Results:
- A mechanism to realize UGRs by tuning interband coupling due to symmetry breaking was identified.
- UGRs along high-symmetric lines were found to correspond to phase singularities, acting as topological indices.
- The interplay between UGRs and non-Hermitian degeneracies was elaborated.
Conclusions:
- UGRs exhibit topological characteristics in their generation, evolution, and annihilation.
- The findings open new avenues for precise light manipulation using photonic crystals.
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