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Fabrication and Characterization of Disordered Polymer Optical Fibers for Transverse Anderson Localization of Light
Published on: July 29, 2013
Coherent forward scattering peak induced by Anderson localization
T Karpiuk1, N Cherroret, K L Lee
1Centre for Quantum Technologies, National University of Singapore, 3 Science Drive 2, Singapore 117543, Singapore.
Physical Review Letters
|December 11, 2012
Summary
Numerical simulations reveal a new forward interference peak at Anderson localization onset. This peak, alongside coherent backscattering, confirms Anderson localization and is linked to Heisenberg time within the localization volume.
Area of Science:
- Condensed matter physics
- Wave phenomena in disordered systems
Background:
- Anderson localization describes the cessation of wave propagation in disordered media.
- Coherent backscattering is a known signature of wave interference in random potentials.
Purpose of the Study:
- To identify and characterize new signatures of Anderson localization.
- To investigate the momentum distribution of wave packets in random potentials.
Main Methods:
- Numerical simulations of wave packet propagation.
- Analysis of momentum distributions.
- Application of maximally crossed diagrams for theoretical explanation.
Main Results:
- A novel interference peak observed in the forward direction of the momentum distribution.
- This forward peak emerges at the localization time.
- The signal's growth scales with the Heisenberg time of the localization volume.
Conclusions:
- The forward interference peak, together with coherent backscattering, provides robust evidence for Anderson localization.
- The observed phenomenon offers new insights into wave transport in disordered systems.
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