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Updated: Jun 10, 2026
11:08
Fabrication And Characterization Of Photonic Crystal Slow Light Waveguides And Cavities
Published on: November 30, 2012
Planar photonic crystal cavities with far-field optimization for high coupling efficiency and quality factor
S L Portalupi1, M Galli, C Reardon
1Dipartimento di Fisica A. Volta, Università di Pavia, via Bassi 6, 27100 Pavia, Italy.
Optics Express
|August 20, 2010
Summary
Researchers optimized silicon photonic crystal cavities for efficient light emission. Modifying cavity designs significantly improved light coupling, crucial for nano-lasers and single-photon sources.
Area of Science:
- Photonics
- Materials Science
- Optical Engineering
Background:
- Planar photonic crystal (PhC) cavities are crucial for controlling light emission.
- Optimizing both quality (Q) factor and coupling efficiency is challenging.
- Existing designs often struggle with efficient in- and out-coupling.
Purpose of the Study:
- To design and experimentally assess PhC cavities for optimized far-field emission.
- To investigate the trade-off between Q factor and coupling efficiency.
- To enhance vertical light coupling for telecommunications wavelengths.
Main Methods:
- Design and fabrication of L3, L5, and L7 type PhC cavities in silicon membranes.
- Experimental assessment using resonant scattering measurements.
- Theoretical prediction and experimental validation of modified hole structures.
Main Results:
- Modification of PhC cavity holes significantly altered far-field emission patterns.
- Substantial increase in vertical coupling efficiency was achieved.
- An L7-type cavity demonstrated a Q factor of ~62000 and improved resonant scattering by two orders of magnitude.
Conclusions:
- Optimized PhC cavities offer a promising route to high-efficiency light emission.
- The L7 cavity design provides an optimal balance between Q factor and coupling.
- These findings are vital for developing advanced light-emitting devices like nano-lasers and single-photon sources.
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