在氧化物异构结构中的3D氧空位分布和缺陷属性关系
Kasper A Hunnestad1,2,3, Hena Das4, Constantinos Hatzoglou1
1Department of Materials Science and Engineering, NTNU Norwegian University of Science and Technology, Trondheim, 7491, Norway.
Nature communications
|June 26, 2024
概括
在氧化物异构结构中的氧气空缺用原子探头断层扫描在3D中得到量化. 它们的有序分布稳定了多铁超级网中的铁电和铁磁性质.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 固态化学 固态化学
背景情况:
- 氧化物异构结构表现出多样化的物理性质,包括非传统的超导和拓极序.
- 氧含量变化显著影响氧化物中的电子相关现象,但量化其影响是具有挑战性的.
研究的目的:
- 要量化氧气空缺在多铁 (LuFeO3) 9 / LuFe2O4) 1超级网格中的分布.
- 为了将氧气空位分布与电磁性质相关联.
- 在氧化物异构结构中建立一个3D,原子尺度的缺陷量化方法.
主要方法:
- 原子探头断层扫描被用来测量化学成分和映射氧气空缺分布.
- 分析重点是将3D空位安排与铁电和铁磁性质相关联.
主要成果:
- 观察到氧气空缺形成一个分层的3D结构,局部密度为~10^14 cm^-2.
- 空位排序与铁磁性LuFe2O4层保持一致,由减少的局部形成能量驱动.
- 氧气空缺在稳定LuFeO3中的铁电领域和LuFe2O4.4中的铁磁性方面发挥着至关重要的作用.
结论:
- 在研究的超级格子中,氧空位和多铁体秩序之间存在明显的相互作用.
- 开发的方法允许精确的3D量化氧缺陷.
- 这为通过缺陷工程来控制氧化物异构结构的特性提供了新的途径.
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