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Updated: Aug 26, 2025
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Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
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Unconventional Ferroelectricity with Quantized Polarizations in Ionic Conductors: High-Throughput Screening.
Xuechen Wang1, Yangyang Ren1,2, Menghao Wu1
1School of Physics and School of Chemistry, Institute of Theoretical Chemistry, Huazhong University of Science and Technology, Wuhan430074, China.
The Journal of Physical Chemistry Letters
|October 6, 2022
Summary
Researchers discovered a new type of ferroelectricity in ionic conductors, driven by long-range ion displacements and vacancies. This phenomenon can create giant, quantized polarizations in materials like KSnS4 and Na4SnS4.
Area of Science:
- Solid-state physics
- Materials science
- Crystallography
Background:
- Ferroelectricity typically arises from asymmetric ion displacement within a unit cell.
- Ionic conductors feature mobile ions but usually possess symmetrical, nonpolar lattices.
- Existing ionic conductors are generally nonpolar due to nondirectional ionic bonding.
Purpose of the Study:
- To explore unconventional ferroelectricity in ionic conductors.
- To investigate the induction of giant polarization by ion vacancies.
- To identify materials exhibiting long ion displacement ferroelectricity.
Main Methods:
- High-throughput screening of candidate materials.
- Ab initio calculations to verify theoretical predictions.
- Experimental validation using KSnS4 and Na4SnS4.
Main Results:
- Identified 35 candidate materials for unconventional ferroelectricity.
- Demonstrated long ion displacement ferroelectricity in KSnS4 and Na4SnS4.
- Observed quantized polarization changes with integer quantum number shifts during switching.
Conclusions:
- Propose a new mechanism for ferroelectricity via combined displacive modes in ionic conductors.
- Show that ion vacancies can induce giant polarization in these systems.
- Highlight the potential for large polarizations through experimentally achievable ion vacancy densities.
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