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Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
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Large Polarization Switching and High-Temperature Magnetoelectric Coupling in Multiferroic GaFeO3 Systems
Hui Wang1, Yang Zhang1, Koki Tachiyama2
1State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Science, Shanghai 200050, China.
Inorganic Chemistry
|December 15, 2020
Summary
Scandium doping significantly reduces leakage current in Gallium Iron Oxide (GaFeO3)-type multiferroics. This enables large ferroelectric polarization switching and magnetoelectric coupling near room temperature.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Solid State Chemistry
Background:
- GaFeO3-type iron oxides are promising multiferroics with potential for room-temperature applications.
- High leakage current and synthesis challenges hinder their practical use, limiting ferroelectric switching and magnetoelectric coupling.
Purpose of the Study:
- To overcome limitations in GaFeO3-type multiferroics by synthesizing high-quality Sc-doped single crystals.
- To investigate the effects of Sc doping on electrical and magnetic properties, particularly leakage current and ferroelectric switching.
Main Methods:
- Single crystals of Sc-doped GaFeO3 (ScxGa1-xFe1-xO3, x = 0-0.3) were successfully prepared using the floating zone method.
- Electrical and magnetic properties, including leakage current, ferroelectric polarization, and magnetic anisotropy, were characterized.
Main Results:
- Sc doping (x ≥ 0.05) reduced leakage current by 10^4 times compared to undoped crystals.
- Sc-doped crystals showed large ferroelectric polarization switching along the c-axis (22-25 μC/cm²), approaching theoretical predictions.
- Ferrimagnetism with magnetic anisotropy along the a-axis was observed, along with magnetic-field-induced polarization modulation at 100 K.
Conclusions:
- Sc doping is crucial for enhancing the performance of GaFeO3-type multiferroics by mitigating leakage current.
- The study demonstrates the potential for achieving significant ferroelectric polarization and magnetoelectric coupling in Sc-doped GaFeO3 at higher temperatures.
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