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High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal
Published on: October 31, 2019
Nematic liquid crystal dynamics under applied electric fields
B F de Oliveira1, P P Avelino, F Moraes
1Centro de Física do Porto, Rua do Campo Alegre 687, 4169-007 Porto, Portugal.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|January 15, 2011
Summary
This study explores how electric fields affect liquid crystal textures. Different electric field orientations and dielectric anisotropies create unique defect patterns in the evolving texture network.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Soft Matter Physics
Background:
- Liquid crystal textures exhibit complex coarsening dynamics.
- Applied electric fields can influence these dynamics.
- Understanding defect formation is crucial for controlling material properties.
Purpose of the Study:
- To investigate the coarsening dynamics of two-dimensional nematic liquid crystal textures under applied electric fields.
- To analyze the impact of electric field orientation and dielectric anisotropy on texture evolution.
- To characterize the types of defects produced by electric field pulses.
Main Methods:
- Numerical simulations using a publicly available liquid crystal algorithm.
- Consideration of both positive and negative dielectric anisotropies.
- Examination of electric fields applied parallel and perpendicular to the lattice.
Main Results:
- Applied electric fields significantly alter the coarsening dynamics of liquid crystal textures.
- The orientation of the electric field and the sign of dielectric anisotropy dictate the types of defects formed.
- Electric field pulses influence the characteristic length scale and network properties.
Conclusions:
- Electric field manipulation offers a pathway to control defect formation in liquid crystal textures.
- The study provides insights into the fundamental physics governing liquid crystal behavior under external fields.
- Results are relevant for applications requiring tailored liquid crystal microstructures.
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