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Updated: Jun 28, 2026
06:26
Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
Transition from longitudinal to transversal patterns in an anisotropic system
Martin May1, Wolfgang Schöpf, Ingo Rehberg
1Experimentalphysik V, Universität Bayreuth, D-95440 Bayreuth, Germany. martin.may@uni-bayreuth.de
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|November 13, 2008
Summary
Periodic stripe patterns in low-conductivity nematic liquid crystals are explored. The dielectric electroconvection mode persists to low frequencies, revealing a Lifschitz point and a crossover to flexoelectric domains at 0.1 Hz.
Area of Science:
- Physics
- Materials Science
- Soft Matter Physics
Background:
- Nematic liquid crystals exhibit complex behaviors under electric fields.
- Electroconvection and flexoelectricity are key phenomena in liquid crystal physics.
Purpose of the Study:
- To investigate periodic stripe patterns in nematic liquid crystals under low-frequency electric fields.
- To analyze the dielectric electroconvection mode and its persistence at low frequencies.
- To characterize the crossover from electroconvection to flexoelectric domains.
Main Methods:
- Application of electric fields to thin nematic liquid crystal layers with very low conductivity.
- Observation of pattern formation and analysis of Lifschitz point transitions.
- Theoretical modeling including flexoelectricity to describe onset characteristics.
Main Results:
- The dielectric electroconvection mode persists down to very low driving voltage frequencies.
- A Lifschitz point, indicating a transition from normal to oblique rolls, was detected in the dielectric regime.
- A crossover from electroconvection to flexoelectric domains occurs around 0.1 Hz, showing mixed pattern morphologies.
Conclusions:
- The study elucidates the behavior of nematic liquid crystals under low-frequency electric fields.
- A theoretical model incorporating flexoelectricity accurately describes the observed dielectric convection onset.
- The findings contribute to understanding pattern formation mechanisms in liquid crystals.
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