Related Experiment Video
Updated: Jan 25, 2026
Fabrication of 1-D Photonic Crystal Cavity on a Nanofiber Using Femtosecond Laser-induced Ablation
Published on: February 25, 2017
Helical edge states of topological photonic crystals with line defects
Abstract:
Topologically protected edge states of honeycomb photonic crystals (PCs) have been extensively studied in recent years. Here we propose several optimized two-dimensional PC configurations with distinct line defects introduced by breaking the C6 symmetry of each topological lattice along the interfaces between two different topologies. The spin-flipping nature of the defect modes of these PC configurations is measured, which is expected to offer a novel realization mechanism of quantum spin Hall effect. The line defects can be treated as unidirectional air waveguides due to the characteristic topological properties. We manipulate the coupling effect of two helical edge states with tunable waveguide widths. It shows that the air waveguide has possibility for practical applications because of its suppression of backward scattering and considerable transmission efficiency.
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