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Updated: Jun 27, 2026
11:08
Fabrication And Characterization Of Photonic Crystal Slow Light Waveguides And Cavities
Published on: November 30, 2012
Efficient slow-light coupling in a photonic crystal waveguide without transition region.
T P White1, L C Botten, C Martijn de Sterke
1School of Physics and Astronomy, University of St Andrews, Fife, UK. tom.white@st-andrews.ac.uk
Optics Letters
|November 19, 2008
Summary
Researchers achieved near-perfect coupling into a slow light mode in photonic crystal waveguides. This efficient coupling into the slow mode (group index ng>1000) occurs without needing a transition region.
Area of Science:
- Photonics
- Condensed Matter Physics
- Waveguide Optics
Background:
- Photonic crystal waveguides offer unique light manipulation capabilities.
- Slow light modes in these structures can enhance light-matter interactions.
- Efficiently coupling light into slow modes is crucial for device applications.
Purpose of the Study:
- To investigate the coupling mechanism into a slow mode in photonic crystal waveguides.
- To achieve efficient and broadband coupling without transition regions.
- To understand the role of evanescent modes in this coupling process.
Main Methods:
- Analysis of band structures in photonic crystal waveguides.
- Theoretical modeling of light coupling.
- Numerical simulations to verify coupling efficiency.
Main Results:
- Identified a slow mode near a band structure inflection point with a group index ng > 1000.
- Demonstrated essentially perfect coupling into this slow mode without any transition region.
- Showcased the significant role of an evanescent mode in facilitating boundary condition matching.
Conclusions:
- Efficient coupling into slow light modes is achievable in photonic crystal waveguides.
- Evanescent modes play a critical role in enabling efficient coupling by satisfying boundary conditions.
- This finding opens avenues for novel photonic devices utilizing slow light.
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