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Updated: Jun 23, 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
Optimal percolation of disordered segregated composites.
Niklaus Johner1, Claudio Grimaldi, Thomas Maeder
1LPM, Ecole Polytechnique Fédérale de Lausanne, Station 17, CH-1015 Lausanne, Switzerland. niklaus.johner@epfl.ch
Summary
We studied percolation thresholds in segregated composite systems. An optimal concentration for percolation was found to exist before maximum segregation, driven by competing volume and concentration effects.
Area of Science:
- Materials Science
- Physics
- Statistical Mechanics
Background:
- Percolation theory describes the formation of connected clusters in random systems.
- Segregated systems, common in composite materials, exhibit complex percolation behavior.
- Understanding percolation thresholds is crucial for designing materials with specific properties.
Purpose of the Study:
- To evaluate percolation threshold values in a realistic model of continuum segregated systems.
- To investigate the relationship between segregation and percolation threshold.
- To identify optimal conditions for percolation in segregated composites.
Main Methods:
- Modeling segregated systems with spherical inclusions and penetrable shells.
- Analyzing the behavior of hardcore spherical particles within these systems.
- Evaluating percolation threshold as a function of segregation concentration.
Main Results:
- The percolation threshold is a non-monotonous function of segregation.
- An optimal (minimum) critical concentration for percolation exists before maximum segregation.
- This phenomenon arises from a balance between reduced available volume and increased concentration requirements.
Conclusions:
- Segregation significantly impacts percolation thresholds in composite materials.
- Optimal material design for percolation can be achieved at intermediate segregation levels.
- Findings offer insights into the behavior of existing segregated materials.
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