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Updated: Aug 3, 2026
06:26
Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
Field-induced phase transitions in an antiferroelectric liquid crystal using the pyroelectric effect
1Department of Electronic and Electrical Engineering, Trinity College, University of Dublin, Dublin 2, Ireland and Institute of Crystallography, Russian Academy of Sciences, Leninskii Prospekt 59, 117333 Moscow, Russia.
Summary
This study investigates antiferroelectric liquid crystals (AFLCs) using pyroelectric response measurements. The research elucidates AFLC phase transitions and characterizes an unusual ferrielectric phase, offering insights into their complex behavior.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Physical Chemistry
Background:
- Antiferroelectric liquid crystals (AFLCs) exhibit complex helical polar phases.
- Understanding phase transitions and behavior under external fields is crucial for AFLC applications.
Purpose of the Study:
- To investigate the pyroelectric response of AFLC phases under varying temperature and bias fields.
- To elucidate the nature of antiferroelectric phases and field-induced phase transitions.
- To characterize an unusual ferrielectric phase between SmC* and AF phases.
Main Methods:
- Pyroelectric response measurements as a function of temperature and bias field.
- Analysis of pyroelectric signal across different AFLC phases.
- Application of theoretical models to interpret experimental results.
Main Results:
- Pyroelectric response measurements effectively probe AFLC phases and transitions.
- Threshold fields for field-induced phase transitions were determined.
- The type of field-induced transition from the AF phase is temperature-dependent.
- An unusual ferrielectric phase was identified as an incommensurate phase.
Conclusions:
- Pyroelectric measurements are a valuable tool for studying AFLC phase behavior.
- Field-induced transitions in AFLCs are complex and temperature-sensitive.
- The identified ferrielectric phase aligns with theoretical predictions for incommensurate phases.
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