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Updated: Apr 12, 2026
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High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal
Published on: October 31, 2019
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Electric-field-induced flow-aligning state in a nematic liquid crystal
Jaka Fajar Fatriansyah1, Hiroshi Orihara1
1Division of Applied Physics, Faculty of Engineering, Hokkaido University, Sapporo, Hokkaido 060-8628, Japan.
Summary
Researchers studied shear stress in nematic liquid crystals using electric fields. They identified two distinct states, flow-aligning and non-flow-aligning, controllable by electric fields, impacting material response and relaxation times.
Area of Science:
- Rheology
- Soft Matter Physics
- Materials Science
Background:
- Nematic liquid crystals exhibit complex flow behavior under external fields.
- Understanding director orientation is crucial for predicting material properties.
Purpose of the Study:
- To investigate the shear stress response in nematic liquid crystals under combined shear flow and DC electric fields.
- To characterize the distinct flow-aligning and non-flow-aligning states and their transitions.
Main Methods:
- Measurement of shear stress response to a weak AC electric field probe.
- Application of shear flow and DC electric fields to nematic liquid crystal samples.
- Analysis of director orientation in different flow regimes.
Main Results:
- Two distinct states, flow-aligning and non-flow-aligning, were observed based on director orientation.
- The non-flow-aligning state can be transitioned to the flow-aligning state using a DC electric field.
- Transitions between states showed increased response and prolonged relaxation times.
Conclusions:
- The study demonstrates the controllability of nematic liquid crystal states via electric fields.
- Experimental results in the flow-aligning state are consistent with Ericksen-Leslie theory.
- This research provides insights into the rheological behavior of liquid crystals.
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