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Updated: Jul 11, 2026
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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
Radiating dipoles in photonic crystals
1Department of Physics, University of Toronto, 60 St. George Street, Toronto, Ontario, Canada M5S 1A7 and Institut fur Theorie der Kondensierten Materie, Universitat Karlsruhe, P.O. Box 6980, 76128 Karlsruhe, Germany.
Summary
We modeled radiation dynamics in photonic crystals using a coupled harmonic oscillator system. This approach accurately predicts emission spectra and decay times for embedded dipole antennas.
Area of Science:
- Condensed Matter Physics
- Quantum Optics
- Electromagnetism
Background:
- Understanding radiative emission from antennas in photonic crystals is crucial for controlling light-matter interactions.
- Previous models often simplified the complex electromagnetic environment within photonic crystals, limiting predictive accuracy.
- Photonic crystals offer unique band structures that can modify the spontaneous emission rates of embedded emitters.
Purpose of the Study:
- To develop a theoretical model for the radiation dynamics of a dipole antenna within a photonic crystal.
- To incorporate realistic photonic crystal properties, such as Bloch waves and dispersion relations, into the model.
- To provide a predictive tool for experimental studies in both microwave and optical regimes.
Main Methods:
- Modeled the system as a harmonic oscillator coupled to a non-Markovian bath of oscillators representing the photonic crystal's electromagnetic vacuum.
- Derived realistic coupling constants based on the natural modes (Bloch waves) and dispersion relation of the photonic crystal.
- Validated the model by reproducing known results for decay times and emission spectra in simplified systems.
Main Results:
- The model successfully reproduces well-known results for decay times and emission spectra.
- Realistic coupling constants derived from photonic crystal band structures were incorporated.
- The approach allows direct integration of band structure computations into radiative emission studies.
Conclusions:
- The developed model provides a predictive and interpretative framework for radiative emission from antennas in photonic crystals.
- This method enables the study of emission dynamics considering realistic photonic crystal environments.
- The tool is applicable to experiments in both microwave and optical frequencies.
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