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Updated: Jun 26, 2026
09:19
Fabrication and Characterization of Disordered Polymer Optical Fibers for Transverse Anderson Localization of Light
Published on: July 29, 2013
Ultrashort pulse propagation and the Anderson localization
S Gentilini1, A Fratalocchi, L Angelani
1Department of Physics, University Sapienza, Rome, Italy.
Optics Letters
|January 17, 2009
Summary
We simulated light pulse propagation in random media using Maxwell equations. Our findings reveal how pulse velocity and decay change with increasing refractive index and scattering.
Area of Science:
- Computational physics
- Wave propagation
- Photonics
Background:
- Understanding light propagation in disordered media is crucial for applications like optical imaging and materials science.
- Previous studies often relied on approximations, limiting accuracy for short pulses and complex scattering scenarios.
Purpose of the Study:
- To accurately simulate the dynamics of a 10 femtosecond light pulse in a random medium.
- To investigate the relationship between pulse energy velocity, decay time, and localization length.
- To analyze the impact of increasing refractive index on light pulse behavior in disordered materials.
Main Methods:
- Direct numerical solution of the three-dimensional Maxwell equations.
- Utilizing molecular dynamics to generate a realistic distribution of spherical scatterers.
- Employing a parallel finite-difference time-domain (FDTD) code for vectorial wave propagation simulation.
Main Results:
- Calculated the disorder-averaged energy velocity of the light pulse.
- Determined the decay time of the transmitted pulse.
- Quantified the pulse dynamics as a function of localization length for varying refractive indices.
Conclusions:
- The study provides a direct, accurate simulation of short pulse propagation in random media.
- Established quantitative relationships between pulse characteristics and medium properties (refractive index, scattering).
- Offers insights into light localization phenomena and energy transport in disordered photonic materials.
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