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Updated: Nov 22, 2025
07:03
Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
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Room-Temperature Antiferroelectricity in Multiferroic Hexagonal Rare-Earth Ferrites
Jun Kasahara1, Tsukasa Katayama1, Shishin Mo1
1Department of Chemistry, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan.
ACS Applied Materials & Interfaces
|January 11, 2021
Summary
Researchers expanded the antiferroelectric (AFE) phase temperature range in hexagonal rare-earth manganites to room temperature. This discovery in DyFeO3 films enables new studies of multiferroic microstructures and magnetoelectric properties.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Solid State Chemistry
Background:
- Hexagonal rare-earth manganites (h-RMnO3) exhibit promising multiferroic properties.
- Antiferroelectric (AFE) phase switching by electric field is a key feature, but previously limited to 60-160 K.
Purpose of the Study:
- To expand the temperature range of the AFE phase in h-RMnO3 materials.
- To investigate the structural origins of the AFE phase at higher temperatures.
- To explore magnetoelectric coupling in the expanded AFE phase.
Main Methods:
- Epitaxial stabilization of h-DyFeO3 thin films.
- Room-temperature scanning transmission electron microscopy (STEM).
- Magnetocapacitance measurements at various magnetic fields.
Main Results:
- Successfully expanded the AFE phase temperature range to 10-300 K in h-DyFeO3 films.
- Identified a nanomosaic structure of AFE (P3̅c1) and ferroelectric (P63cm) domains (1-10 nm) as the origin.
- Observed weak ferromagnetism and magnetocapacitance, with an M-shaped curve below 10 K indicating unusual magnetoelectric coupling.
Conclusions:
- Epitaxial stabilization is effective in extending the AFE phase range in h-DyFeO3.
- The nanomosaic structure, stabilized by a low c/a ratio due to Dy3+ ionic radius, is crucial for the AFE phase.
- The observed magnetoelectric coupling suggests potential for novel device applications.
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