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Updated: Jan 15, 2026
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Chemical Synthesis of Porous Barium Titanate Thin Film and Thermal Stabilization of Ferroelectric Phase by Porosity-Induced Strain
Published on: March 27, 2018
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Anisotropic Ferroelectric Switching Dynamics in Layered Bi2WO6
Deokyoung Kang1,2, Jaegyu Kim1,2, Ching-Che Lin1,2
1Department of Materials Science and Engineering, University of California, Berkeley, California 94720, United States.
ACS Nano
|October 7, 2025
Summary
Epitaxial Bi2WO6 thin films show defect-guided ferroelectric domain switching. Planar defects influence polarization behavior, enabling stable multilevel switching with high retention.
Area of Science:
- Materials Science
- Solid State Physics
- Crystallography
Background:
- Layered perovskite oxides are promising ferroelectric materials.
- Their complex structure and switching mechanisms need further study.
Purpose of the Study:
- Investigate structural distortions and their effect on polarization switching in Aurivillius-phase Bi2WO6 thin films.
- Understand defect-guided domain switching mechanisms.
Main Methods:
- Epitaxial growth of Aurivillius-phase Bi2WO6 thin films.
- Structural analysis to identify crystallographic tilts and planar defects.
- Stroboscopic piezoresponse force microscopy to observe domain dynamics.
Main Results:
- Crystallographic tilts observed, linked to planar defects at step edges.
- Polarization switching suppressed as electric field rotates away from step edges.
- Defect-guided domain nucleation and propagation along step edges observed.
- Domain-wall pinning at defects enables stable multilevel polarization switching.
Conclusions:
- Planar defects significantly impact ferroelectric domain switching in Bi2WO6 films.
- Defect-guided switching enables stable multilevel polarization with low variation and long retention.
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