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Updated: Jun 25, 2026
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High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal
Published on: October 31, 2019
Ambidextrous bend patterns in free-standing polar smectic- CP{F} films
Alexey Eremin1, Alexandru Nemeş, Ralf Stannarius
1Otto-von-Guericke-Universität Magdeburg, IEP, Department of Nonlinear Phenomena, Universitätsplatz 2, D-39016 Magdeburg, Germany.
Summary
Ferroelectric smectic films with bent molecules exhibit an unexpected striped pattern. This unique bend deformation arises from molecular structure, not chirality, challenging existing theories.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Liquid Crystals
Background:
- Bent-shaped molecules in ferroelectric smectic films can exhibit complex director configurations.
- Previous studies identified twist-bend instability in similar systems.
Purpose of the Study:
- To investigate the unusual ground state director behavior in ferroelectric smectic-CP{F} films.
- To understand the origin of the observed striped pattern and its relation to molecular properties.
Main Methods:
- Experimental observation of ferroelectric smectic-CP{F} films.
- Analysis of the c-director behavior and bend deformation patterns.
Main Results:
- The ground state director forms a striped pattern with alternating bend deformation, deviating from a uniform state.
- The sense of the bend deformation is independent of the molecular tilt (c-director) and bow (p-director) orientation.
- The observed pattern cannot be explained by spontaneous chiral symmetry breaking due to pre-defined film chirality.
Conclusions:
- The striped bend pattern in ferroelectric smectic films is an unusual phenomenon.
- Molecular structure and synclinic order play a crucial role in defining the film's chirality and director behavior.
- Further theoretical models are needed to fully describe the spontaneous formation of this ambidextrous bend pattern.
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