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Propagating director bend fluctuations in nematic liquid crystals
Anja Humpert1, Michael P Allen2
1Department of Physics, University of Warwick, Coventry CV4 7AL, United Kingdom.
Physical Review Letters
|January 31, 2015
Summary
Molecular simulations reveal that director bend fluctuations in nematic liquid crystals are propagating modes, challenging traditional hydrodynamic models. This finding suggests observable bend fluctuations in experimental liquid crystal systems.
Area of Science:
- Soft Matter Physics
- Materials Science
- Computational Physics
Background:
- Nematic liquid crystals exhibit complex director dynamics.
- Current hydrodynamic theories generally describe director modes as overdamped.
Purpose of the Study:
- To investigate the nature of director bend fluctuations in nematic liquid crystals using molecular simulations.
- To challenge the prevailing understanding of nematic hydrodynamics.
Main Methods:
- Utilized standard, coarse-grained, nematic liquid crystal models.
- Performed molecular simulations to analyze director fluctuation modes.
Main Results:
- Demonstrated that director bend fluctuations are propagating modes, not overdamped.
- Identified physical parameters influencing this behavior within nematodynamics.
Conclusions:
- The generally accepted picture of overdamped director modes in nematic hydrodynamics is challenged.
- Propagating bend fluctuations may be experimentally observable in certain liquid crystal systems.
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