铁电薄膜中的迷宫域模式的反向过渡
Y Nahas1, S Prokhorenko2, J Fischer3
1Physics Department and Institute for Nanoscience and Engineering, University of Arkansas, Fayetteville, AR, USA. yousra.nahas@gmail.com.
Nature
|January 3, 2020
概括
铁电超薄膜呈现反向转变,随着温度的增加,从迷宫变为条纹域模式. 这种由域壁和缺陷驱动的现象为铁电技术提供了新的设计原则.
科学领域:
- 材料科学
- 凝聚物质物理学
- 晶体学
背景情况:
- 阶段分离驱动材料中的图案形成.
- 在各种材料中观察到反向转换,这是一个罕见的对称性破坏现象,但不是铁电氧化物.
- 铁电领域对于设备的功能至关重要.
研究的目的:
- 为了研究铁电氧化物的反二极转变.
- 在超薄膜中探索铁电领域的自组合.
- 了解域壁和拓缺陷在相位过渡中的作用.
主要方法:
- 超薄Pb{Zr0.4Ti0.6) O3薄膜的临界下火.
- 温度依赖的域结构分析.
- 计算模型和实验观测 (例如,在BiFeO3).
主要成果:
- 在火后观察到铁电域的非平衡自我组装成迷宫模式.
- 证明了从迷宫到平行条形域的反向过渡随着温度的增加.
- 将相序归因于增强的域壁和缺陷驱动的域粗.
结论:
- 在铁电氧化物中实验实现了反二极转换.
- 这种现象为铁电膜和设备提供了新的设计原则.
- 拓缺陷在驱动域进化和相位过渡方面发挥着关键作用.
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