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High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal
Published on: October 31, 2019
Field-induced texture transitions in a bent-core nematic liquid crystal
R Stannarius1, A Eremin, M-G Tamba
1Institute of Experimental Physics, Otto-von-Guericke-University, Universitätsplatz 2, D-39106 Magdeburg, Germany.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|February 1, 2008
Summary
Bent-core mesogens exhibit persistent texture changes in nematic phases when exposed to strong electric fields. These induced states, observable as coexisting domains, can be stabilized, revealing a metastable biaxial state.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Electro-optics
Background:
- Bent-core mesogens are known for unique liquid crystalline properties.
- Electro-optic effects in nematic phases are crucial for display technologies.
- Understanding field-induced phase transitions is key to material manipulation.
Purpose of the Study:
- To investigate field-induced persistent texture transitions in bent-core nematic phases.
- To characterize the optical and electric properties of field-induced metastable states.
- To explore the coexistence and stabilization of different domain states.
Main Methods:
- Electro-optic experiments applying external electric fields (approx. 10^5 V/m).
- Observation of texture transitions in planar and homeotropic sandwich cells.
- Analysis of optical and electric properties of induced and original states.
Main Results:
- An electric field of ~10^5 V/m induces persistent texture transitions in bent-core nematic phases.
- Field-induced metastable states coexist with the ground state in domains for up to an hour.
- Metastable biaxial states and inversion walls are observed, with stabilization possible in moderate fields.
Conclusions:
- Bent-core nematic phases exhibit field-induced metastable states with distinct properties.
- The observed phenomena suggest a transition to a metastable biaxial state.
- Domain dynamics and stabilization offer insights into controlling liquid crystal textures.
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