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Effect of external field on coherent backscattering in nematics
1Department of Physics, St. Petersburg State University, St. Petersburg, Russia.
Optics Letters
|February 21, 2012
Summary
This study reveals a direct link between extraordinary wave scattering and magnetic coherence length in nematic liquid crystals. Monte Carlo simulations show minimal impact on coherent backscattering despite significant magnetic field changes.
Area of Science:
- Condensed Matter Physics
- Soft Matter Physics
- Optics
Background:
- Nematic liquid crystals exhibit complex optical properties influenced by magnetic fields.
- Understanding light scattering phenomena is crucial for device applications.
Purpose of the Study:
- To establish an explicit relationship between scattering length and magnetic coherence length in a simplified liquid crystal model.
- To investigate the effect of magnetic fields on coherent backscattering, considering orientational fluctuations and anisotropy.
Main Methods:
- Utilized the optical theorem for a one-elastic-constant model of nematic liquid crystals.
- Performed Monte Carlo simulations of coherent backscattering.
- Incorporated long-range orientational fluctuations and scattering length anisotropy into simulations.
Main Results:
- Derived an explicit relationship between the extraordinary wave mode's scattering length and the magnetic coherence length.
- Observed that the coherent backscattering peak is relatively insensitive to magnetic field variations over several orders of magnitude.
- Scattering length anisotropy and orientational fluctuations were accounted for in the simulations.
Conclusions:
- The optical theorem provides a direct analytical link between key physical parameters in nematic liquid crystals.
- Coherent backscattering is robust against changes in magnetic field strength in this system.
- The findings contribute to the theoretical understanding of light propagation and scattering in magnetic liquid crystals.
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