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Using Microwave and Macroscopic Samples of Dielectric Solids to Study the Photonic Properties of Disordered Photonic Bandgap Materials
Published on: September 26, 2014
Cluster coherent potential approximation for disordered photonic crystals using photonic Wannier functions
Martin Köhl1, Christian Wolff, Kurt Busch
1Institut für Theoretische Festkörperphysik and DFG-Center for Functional Nanostructures (CFN), Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany. mkoehl@tfp.uni‑karlsruhe.de
Optics Letters
|February 21, 2012
Summary
This study introduces a new method for analyzing disordered photonic crystals (PhCs) using cluster coherent potential approximation (CPA). The approach accurately models multiple scattering effects, crucial for understanding random lasing and fabrication defects in PhCs.
Area of Science:
- Condensed Matter Physics
- Photonics
- Materials Science
Background:
- Disordered photonic crystals (PhCs) exhibit unique optical properties influenced by structural imperfections.
- Understanding the effects of disorder is crucial for applications like random lasing and fabricating functional PhCs.
Purpose of the Study:
- To develop and validate a theoretical framework for analyzing disordered PhCs.
- To incorporate multiple scattering effects from defects within the coherent potential approximation (CPA).
Main Methods:
- Combination of photonic Wannier functions and the coherent potential approximation (CPA).
- Development of a real-space cluster CPA that ensures causality and proper symmetry.
- Inclusion of multiple scattering effects from both individual and neighboring defects.
Main Results:
- The study provides the theoretical foundation for a causal, symmetry-enforcing real-space cluster CPA.
- Results demonstrate the calculation of the density of states for disordered PhCs under various disorder types.
- The method effectively captures essential multiple scattering phenomena, particularly for strong defects.
Conclusions:
- The developed real-space cluster CPA offers a robust tool for investigating disordered PhCs.
- The findings are relevant for advancing random lasing technologies and analyzing fabrication imperfections.
- This work provides a theoretical basis for designing and understanding PhCs with controlled disorder.
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