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Updated: Jan 23, 2026
13:02
Fabrication of 1-D Photonic Crystal Cavity on a Nanofiber Using Femtosecond Laser-induced Ablation
Published on: February 25, 2017
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Topological beam-splitting in photonic crystals
Optics Express
|June 6, 2019
Summary
Researchers designed a novel passive wave splitter using geometric arrangements of Indium Phosphide dielectric pillars. This breakthrough enables efficient three-way beam splitting for electromagnetic waves in transverse electric and magnetic polarizations.
Area of Science:
- Electromagnetism
- Photonics
- Materials Science
Background:
- Topological valleytronics typically uses hexagonal lattices.
- Achieving three-way beam splitting requires specific lattice geometries.
Purpose of the Study:
- To engineer a passive wave splitter for three-way beam splitting.
- To investigate the role of lattice structure in beam splitting.
- To utilize accidental Dirac cones for wave transport.
Main Methods:
- Designing passive wave splitters using Indium Phosphide dielectric pillars in air.
- Employing square lattice structures for periodic cell extension.
- Utilizing accidental Dirac cones for wave splitting and transport around bends.
- Conducting full scattering simulations to validate designs.
Main Results:
- Demonstrated three-way beam splitting is achievable with square, not hexagonal, lattices.
- Identified specific pillar arrangements (triangle vs. square) within cells for splitting.
- Showcased the mechanism of splitting and its absence in certain configurations.
- Validated the effectiveness of the proposed geometric designs through simulations.
Conclusions:
- Geometric design of dielectric pillar arrays can achieve passive three-way electromagnetic beam splitting.
- Square lattices are essential for enabling three-way splitting, unlike hexagonal lattices.
- Accidental Dirac cones provide a mechanism for efficient wave transport around sharp bends.
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