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Updated: Jun 28, 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
Photon delocalization transition in dimensional crossover in layered media
Sheng Zhang1, Jongchul Park, Valery Milner
1Department of Physics, Queens College, The City University of New York, Flushing, New York 11365, USA.
Physical Review Letters
|November 13, 2008
Summary
Optical propagation in random media transitions from localization to diffusion. This crossover is driven by changes in wave interaction dimensionality and occurs when lateral wave spread matches transverse coherence length.
Area of Science:
- Physics
- Optics
- Condensed Matter Physics
Background:
- Random layered media exhibit complex wave propagation phenomena.
- Understanding the transition between different propagation regimes is crucial for controlling light transport.
Purpose of the Study:
- To investigate the crossover in optical propagation from localization to diffusion in random layered media.
- To identify the critical condition governing this transition.
Main Methods:
- Studying wave propagation in random layered media with nonuniform layer thickness.
- Analyzing the transformation of wave-sample interaction from 1D to 3D.
- Measuring the lateral spread of the wave and the transverse coherence length.
Main Results:
- Observed a crossover from localized to diffusive optical propagation.
- The transition is induced by increasing the dimensionality of wave-sample interaction.
- The crossover point is defined by the equality of lateral wave spread and transverse coherence length.
Conclusions:
- Nonuniformity in layer thickness drives a transition in wave propagation dimensionality.
- This dimensionality change leads to a crossover from localization to diffusion.
- The transverse coherence length serves as a critical parameter for this propagation regime crossover.
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