室温极性铁磁体ScFeO3从高压正弦波矿相转变为高压正弦波矿相
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
概括
研究人员合成了一种新的ScFeO3材料,在室温下具有铁电和磁性. 这一发现为开发用于高温应用的先进多铁材料提供了新的途径.
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
- 晶体学 晶体学是指结晶学.
背景情况:
- 在室温下表现出磁性和铁电性质的多铁材料非常受欢迎,但合成起来很困难.
- 现有的多铁材料在环境温度下往往缺乏强大的性能.
研究的目的:
- 合成和描述一种新的LiNbO3型ScFeO3相与共存的铁电和磁顺序.
- 研究合成材料的结构性,磁性和铁电性质.
- 建立一个创建高温多铁材料的战略.
主要方法:
- 高压和高温合成. 高压和高温合成.
- 同步X射线和中子粉体衍射用于结构分析.
- 高角环状暗场扫描传输电子显微镜 (HAADF-STEM) 用于成像.
- 测量磁感应度的测量.
主要成果:
- 成功合成了具有极性R3c对称性的转移稳定的LiNbO3型ScFeO3相.
- 在六边形c轴上观察到100μC/cm2的大量自发偏振.
- 鉴定出弱铁磁性,其 Néel 温度 (TN) 为 545 K,这是由于倾斜的反铁磁性排序.
- 建立了TN和Fe-O-Fe键角之间的相关性,受A位点离子大小和八面体倾斜的影响.
结论:
- LiNbO3型的ScFeO3是首个在室温远高于室温的磁性排序的例子.
- 该研究提供了一种多功能策略,用于在高温下设计具有共存铁电和铁磁性的多铁材料.
- 八面体倾斜,由A位点离子大小控制,在通过超交互相互作用的磁性过渡中起着至关重要的作用.
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