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Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
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Polymer-disordered liquid crystals: susceptibility to an electric field
Lena M Lopatina1, Jonathan V Selinger1
1Liquid Crystal Institute, Kent State University, Kent, Ohio 44242, USA.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|February 4, 2014
Summary
Disordered polymer networks create glassy liquid crystals. Electric fields induce significant, stable orientational order, with simulations matching analytic predictions for electro-optic applications.
Area of Science:
- Materials Science
- Condensed Matter Physics
Background:
- Nematic liquid crystals in disordered polymer networks exhibit a glassy state due to disrupted long-range order.
- Application of electric fields induces substantial and stable orientational order in these systems.
Purpose of the Study:
- To understand the behavior of liquid crystals within disordered polymer networks under electric fields.
- To visualize domain structures and calculate the field-induced orientational response.
- To predict domain size and estimate field-induced order using analytic methods.
Main Methods:
- Computer simulations of liquid crystals in disordered polymer networks.
- Visualization of the resulting domain structures.
- Calculation of the system's response to an applied electric field.
- Application of an Imry-Ma-like theoretical approach.
Main Results:
- Simulations successfully reproduced the glassy state and field-induced orientational order.
- The domain structure was visualized and analyzed.
- Analytic predictions for domain size and field-induced order showed agreement with simulation results.
- The temperature independence of the induced order was observed.
Conclusions:
- The study validates simulation and analytic models for liquid crystals in disordered polymer networks.
- The findings provide insights into optimizing these materials for electro-optic applications.
- A combined simulation and theoretical approach effectively explains the observed phenomena.
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