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Updated: Jan 9, 2026
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Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
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Van Der Waals Order-Disorder Type Ferroelectric VOCl2 with Unusual Polarization Switching.
Jiapeng Wang1,2, Dong Wang3, Zhenjie Guan1
1School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China.
Journal of the American Chemical Society
|December 4, 2025
Summary
Vanadium oxychloride (VOCl2) is a new ferroelectric material with a wide thermal hysteresis and high Curie temperature. Its unique properties enable tunable polarization under pressure, advancing programmable phase-change devices.
Area of Science:
- Materials Science
- Solid State Physics
- Crystallography
Background:
- Order-disorder transitions are key for tailoring ferroelectric properties.
- Existing ferroelectrics often have limitations like low Curie temperatures and narrow thermal hysteresis.
- These limitations restrict their use in advanced memory technologies.
Purpose of the Study:
- To discover and characterize new van der Waals order-disorder ferroelectrics.
- To investigate the tunability of ferroelectric polarization in VOCl2 under external stimuli.
- To explore the potential of VOCl2 for next-generation programmable devices.
Main Methods:
- Identification of VOCl2 as a novel van der Waals ferroelectric.
- Experimental measurement of thermal hysteresis and Curie temperature.
- Application of hydrostatic pressure to induce and switch polarization.
Main Results:
- VOCl2 exhibits a wide thermal hysteresis (220 K) and high Curie temperature (440 K).
- Lattice expansion accompanies the disorder-to-order transition.
- Hydrostatic pressure induces irreversible in-plane polarization at 2.3 GPa and reversible switching to out-of-plane at 8.0 GPa.
Conclusions:
- VOCl2 presents a promising material for order-disorder ferroelectrics.
- Its significant thermal hysteresis and pressure-tunable polarization offer advantages for device applications.
- This work opens avenues for programmable phase-change devices with enhanced operating windows.
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