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Updated: Jul 3, 2026
10:35
Using Microwave and Macroscopic Samples of Dielectric Solids to Study the Photonic Properties of Disordered Photonic Bandgap Materials
Published on: September 26, 2014
Diffusive transport of light in three-dimensional disordered Voronoi structures
Zeinab Sadjadi1, Mirfaez Miri, Holger Stark
1Institute for Advanced Studies in Basic Sciences (IASBS), P. O. Box 45195-1159, Zanjan 45195, Iran.
Summary
Diffusive light transport in dry foams is clarified. Liquid films, not foam structure, significantly influence light transport, with theoretical values matching experimental data for transport-mean-free path.
Area of Science:
- Physics
- Materials Science
- Optics
Background:
- The mechanism of diffusive light transport in dry foams remains unclear.
- Understanding light scattering in porous media is crucial for various applications.
Purpose of the Study:
- To investigate the origin of diffusive light transport in dry foams.
- To determine the role of liquid films versus foam structure in light diffusion.
Main Methods:
- Modeling foams using 3D Voronoi tessellations with varying disorder.
- Simulating photon random walks based on ray optics and thin film reflectance.
- Analyzing the transport-mean-free path (l*) under different foam configurations.
Main Results:
- The transport-mean-free path (l*) shows minimal dependence on foam topological and geometrical disorder.
- Theoretical l* values align with experimental observations in dry foams.
- Liquid films play a substantial role in diffusive light transport.
Conclusions:
- The detailed structure of foams is not critical for diffusive light transport.
- Liquid films are a primary contributor to light diffusion in dry foams.
- This finding offers insights into light propagation in complex media.
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