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Fabrication and Characterization of Disordered Polymer Optical Fibers for Transverse Anderson Localization of Light
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A self-consistent theory of localization in nonlinear random media
1Laboratoire Kastler Brossel, UPMC-Sorbonne Universités, CNRS, ENS-PSL Research University, Collège de France, 4 Place Jussieu, 75005 Paris, France.
Journal of Physics. Condensed Matter : an Institute of Physics Journal
|November 15, 2016
Summary
A new theory shows that a weak nonlinear potential destroys Anderson localization, replacing it with subdiffusion for spreading wave packets. This creates a subdiffusion-diffusion transition in 3D, unlike unaffected classical diffusion.
Area of Science:
- Condensed matter physics
- Wave phenomena
- Nonlinear dynamics
Background:
- Anderson localization describes the absence of diffusion in disordered systems.
- Nonlinear potentials can significantly alter wave propagation dynamics.
- Understanding transitions in wave behavior is crucial for materials science.
Purpose of the Study:
- To generalize the self-consistent theory of localization.
- To investigate the effect of a weak quadratic nonlinear potential on wave localization.
- To analyze the impact on Anderson localization and diffusion.
Main Methods:
- Generalization of the self-consistent theory of localization.
- Analysis of the wave equation with a nonlinear potential.
- Theoretical prediction for spreading wave packets.
Main Results:
- Anderson localization is destroyed by the nonlinearity.
- Algebraic subdiffusion replaces localization for spreading wave packets.
- Classical diffusion remains unaffected.
- A subdiffusion-diffusion transition emerges in 3D.
Conclusions:
- Nonlinearity fundamentally alters localization phenomena.
- The study predicts a novel transition in 3D systems.
- The generalized theory provides insights into complex wave behavior.
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