铁电中的异常性质是由原子排序引起的.
A M George1, J Iñiguez, L Bellaiche
1Physics Department, University of Arkansas, Fayetteville 72701, USA.
Nature
|September 7, 2001
概括
复杂的矿合金具有显著的介电和压电性能. 最初的计算揭示了原子重新排列,导致这些功能性材料中增强的电力学反应和新的结构阶段.
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
- 计算材料科学科学 计算材料科学
背景情况:
- 复杂的绝缘矿合金具有显著的介电和压电性能.
- 像 (Ba1-xSrx) TiO3 和硫酸 (PZT) 这样的材料在电子设备中至关重要.
- 了解微观结构和异常性质之间的联系是具有挑战性的.
研究的目的:
- 研究矿合金中的原子重排.
- 探索具有改进电机性能的新功能材料的潜力.
- 为了确定异常性质背后的微观机制.
主要方法:
- 使用 ab initio 的计算.
- 在矿合金结构中模拟原子重新排列.
- 分析由此产生的机电反应和结构相.
主要成果:
- 确定了特定的原子重新排列,诱导大电机械反应.
- 发现了由于这些重排而产生的不寻常的结构阶段.
- 阐明了导致这些异常的微观机制.
结论:
- 某些原子重新排列可以同时增强电机性能,并在矿合金中创建新的结构相.
- 这项研究为开发先进的功能性材料提供了一条途径.
- 这些发现提供了对矿结构性质关系的基本见解.
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