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Updated: Apr 1, 2026
11:08
Fabrication And Characterization Of Photonic Crystal Slow Light Waveguides And Cavities
Published on: November 30, 2012
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Dispersion of coupled mode-gap cavities
Optics Letters
|October 1, 2015
Summary
The dispersion in photonic crystal waveguides is asymmetrically explained by frequency-dependent mode profiles, not standard models. This finding stems from incomplete resonance sets in photonic crystal cavities.
Area of Science:
- Photonics
- Condensed Matter Physics
- Optical Engineering
Background:
- Coupled resonator optical waveguides (CROWs) are key components in integrated photonics.
- Photonic crystal (PhC) cavities offer unique light confinement properties.
- Standard tight-binding models often fail to capture complex dispersion phenomena in PhC structures.
Purpose of the Study:
- To investigate the pronounced asymmetric dispersion observed in CROWs based on PhC mode-gap cavities.
- To identify the fundamental physical mechanism responsible for this asymmetry.
- To develop an accurate theoretical model that explains the observed dispersion.
Main Methods:
- Analysis of the coupled resonator optical waveguide system.
- Investigation of the mode profile within photonic crystal cavities.
- Formulation of a dispersive mode coupling model.
Main Results:
- The standard tight-binding model cannot account for the observed asymmetric dispersion.
- The asymmetric dispersion is fundamentally caused by the dispersive nature of the cavity mode profile, where the mode's wave function is frequency-dependent.
- This frequency dependence arises because the photonic crystal cavity resonances do not constitute a complete set.
- The developed dispersive mode coupling model accurately describes the asymmetric dispersion without requiring new free parameters.
Conclusions:
- The inherent dispersive mode profile of PhC cavities is the primary cause of asymmetric dispersion in CROWs.
- A new dispersive mode coupling model provides an accurate theoretical framework for understanding this phenomenon.
- This work offers deeper insights into light propagation in PhC-based waveguides, crucial for photonic device design.
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