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Updated: Apr 21, 2026

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Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
8.0K
室温の極性鉄磁石 ScFeO3 は,高圧オーソロンビックペロブスキート相から変換された
Takahiro Kawamoto1, Koji Fujita, Ikuya Yamada
1Department of Material Chemistry, Graduate School of Engineering, Kyoto University , Katsura, Nishikyo-ku, Kyoto 615-8510, Japan.
Journal of the American Chemical Society
|October 22, 2014
まとめ
研究者らは,室温で鉄電気と磁気の両方の性質を持つ新しいScFeO3材料を合成しました. この発見は,高温アプリケーションのための高度なマルチフェロ材料の開発のための新しい経路を提供します.
科学分野:
- マテリアルサイエンス 材料科学
- 固体物理 固体物理学
- クリスタルグラフィーです.
背景:
- 室温で磁気と電磁性の両方を示すマルチフェロ材料は,非常に求められていますが,合成することは困難です.
- 既存のマルチフェロ材料は,通常,環境温度で堅固な性能を欠いている.
研究 の 目的:
- LiNbO3型ScFeO3相を合成し,共存する鉄電気および磁気配列を特徴づけること.
- 合成された材料の構造的,磁性,および鉄電気的性質を調査する.
- 高温マルチフェロ材料の作成のための戦略を確立する.
主な方法:
- 高圧と高温合成. 高圧と高温合成. 高圧と高温合成. 高圧と高温合成.
- 構造分析のためのシンクロトロンX線と中性子粉の difraktion.
- 高角環状ダークフィールドスキャニングトランスミッション電子顕微鏡 (HAADF-STEM) 画像撮影用.
- 磁気感受性の測定 磁気感受性の測定 磁気感受性の測定
主要な成果:
- 極性R3c対称性を持つメタステーブルなLiNbO3型ScFeO3相を成功して合成した.
- 六角形c軸に沿って100μC/cm2の大きな自発的偏振が観察されました.
- 545 Kのネール温度 (TN) の弱い鉄磁気性が,反鉄磁気順序の傾斜により特定されました.
- TNとFe-O-Fe結合角度との相関が確立され,A位カチオンサイズと八面形の傾きの影響を受けています.
結論:
- LiNbO3型ScFeO3は,室温をはるかに上回る磁気オーダーリングを示す同種の最初の例です.
- この研究は,高温でフェロ電性とフェロ磁性が共存するマルチフェロ材料の設計のための多用途戦略を提供します.
- A位カチオンサイズによって制御される八面形の傾きは,スーパー交換相互作用による磁気移行において重要な役割を果たします.
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