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Anisotropy and interference in wave transport: an analytic theory
B C Kaas1, B A van Tiggelen, A Lagendijk
1FOM Institute for Atomic and Molecular Physics, Kruislaan 407, 1098 SJ Amsterdam, The Netherlands. kaas@amolf.nl
Physical Review Letters
|June 4, 2008
Summary
This study introduces a theory for dielectric anisotropy in scattering media, predicting anisotropic diffusion and energy flow deflection. The findings suggest anisotropy aids in Anderson localization, a key phenomenon in disordered systems.
Area of Science:
- Condensed matter physics
- Optics
- Materials science
Background:
- Random multiple scattering media are crucial in optics and condensed matter.
- Dielectric properties significantly influence light propagation.
- Understanding anisotropy's role is vital for advanced material design.
Purpose of the Study:
- To develop a theoretical framework incorporating dielectric anisotropy in random multiple scattering.
- To investigate the impact of anisotropy on light diffusion and energy flow.
- To explore the relationship between anisotropy and Anderson localization.
Main Methods:
- Development of a new theoretical model for anisotropic scattering media.
- Mathematical analysis of diffuse energy flow and transmittance.
- Investigation of the escape function in anisotropic dielectrics.
Main Results:
- The theory predicts anisotropic diffusion and deflection of diffuse energy flow parallel to anisotropic slabs.
- Integrated transmittance scales with the transport mean free path along the surface normal.
- The escape function deviates from the typical bell shape in anisotropic dielectrics.
Conclusions:
- Dielectric anisotropy fundamentally alters light transport in scattering media.
- Anisotropy is shown to facilitate Anderson localization, a critical quantum phenomenon.
- The developed theory provides new insights into light-matter interactions in complex materials.
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