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Updated: Sep 17, 2025

Fabrication And Characterization Of Photonic Crystal Slow Light Waveguides And Cavities
Published on: November 30, 2012
Topological Singularities and Edge-State Coupling Enable Robust on-Chip Slow Light
Yuqian Wang1, Shengyu Hu1, Zhiwei Guo1
1MOE Key Laboratory of Advanced Micro-structured Materials, School of Physics Sciences and Engineering, Tongji University, Shanghai, 200092, China.
This study demonstrates a robust topological quantum interference (QI) effect on-chip for stable slow light applications. It utilizes topological mechanisms to overcome environmental sensitivities, enabling reliable optical device operation.
Area of Science:
- Quantum optics
- Topological physics
- Nanophotonics
Background:
- Quantum interference (QI) enables advanced optical responses like slow light but is sensitive to environmental changes.
- Existing methods for controlling optical responses face challenges in practical, robust on-chip applications.
Purpose of the Study:
- To experimentally demonstrate a topological QI-like effect for robust slow light on a 1D on-chip system.
- To investigate topological mechanisms that enhance immunity to parameter deviations and structural disturbances.
Main Methods:
- Inducing two distinct topological mechanisms within a composite waveguide.
- Incorporating bright and dark topological edge states.
- Observing electromagnetically induced transparency (EIT) and measuring transmission and group delays.
Main Results:
- Achieved the first experimental demonstration of a topological QI-like effect in a 1D on-chip system.
- Demonstrated robustness of slow light against parameter deviations and structural disturbances using topological charges and edge states.
- Observed EIT and successfully switched between slow and fast light propagation.
Conclusions:
- The developed topological QI platform offers robustness for on-chip optical devices.
- This work opens avenues for exploring novel QI and topological physics in integrated systems.
- Provides a foundation for developing next-generation robust on-chip optical devices.
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