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Updated: Dec 23, 2025
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Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
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Defect-Enhanced Polarization Switching in the Improper Ferroelectric LuFeO3.
Petrucio Barrozo1,2,3, Didrik René Småbråten4, Yun-Long Tang2,3
1Physics Department, Federal University of Sergipe, São Cristóvão, Sergipe, 49100-000, Brazil.
Advanced Materials (Deerfield Beach, Fla.)
|April 30, 2020
Summary
Defects in improper ferroelectric LuFeO3 can significantly lower switching voltage. The coercive field in these materials shows greater frequency dependence than in proper ferroelectrics, indicating primary structural order parameter control.
Area of Science:
- Condensed matter physics
- Materials science
- Solid-state chemistry
Background:
- Improper ferroelectrics like LuFeO3 exhibit unique switching behaviors distinct from proper ferroelectrics.
- Understanding defect-induced modifications is crucial for optimizing ferroelectric device performance.
Purpose of the Study:
- To investigate the switching dynamics of improper ferroelectric LuFeO3.
- To determine the influence of defects on switching voltage and coercive field.
- To compare the frequency dispersion of coercive fields in improper versus proper ferroelectrics.
Main Methods:
- Fabrication of model LuFeO3 thin films under controlled conditions.
- Quasi-static electrical switching measurements.
- Frequency-dependent switching studies.
- Qualitative comparison with first-principles calculations.
Main Results:
- Defects were shown to reduce the quasi-static switching voltage by up to 40%.
- The coercive field exhibited stronger frequency dispersion in LuFeO3 compared to PbTiO3 (a proper ferroelectric).
- Results qualitatively agreed with first-principles calculations.
Conclusions:
- The primary structural order parameter is the key factor governing switching dynamics in improper ferroelectrics.
- Defect engineering offers a viable route to tune the electrical properties of LuFeO3.
- Further research into improper ferroelectric switching mechanisms is warranted.
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