铁电中氧气空缺的延伸平面缺陷[公式:见文本]以及对铁电的影响
Shaohui Qiu1,2, Huaxiang Fu1
1Department of Physics, University of Arkansas, Fayetteville, AR 72701 USA.
Scientific reports
|November 10, 2023
概括
铁电器中的平面氧气空缺显著降低了极化,为极化疲劳和衰老提供了洞察力. 这些缺陷会产生极化死层,影响设备的性能.
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:
- 扩展缺陷,特别是空缺,对于理解铁电 (FE) 现象,如极化疲劳和衰老至关重要.
- 铁电器延长缺陷的行为和影响仍然不太清楚,阻碍了该领域的进展.
研究的目的:
- 为了研究铁电硫酸酸中延伸平面氧气空缺的特性和影响 ([公式:见文本]).
- 阐明不同氧空电荷状态 ([公式:见文本],[公式:见文本],[公式:见文本]) 在铁电行为中的作用.
- 提供理论证据,将平面氧空隙与极化疲劳和印记现象联系起来.
主要方法:
- 利用密度函数理论 (DFT) 来建模和分析铁电材料的电子结构和能量特性.
- 应用了现代极化理论来量化空缺职位对铁电极化的影响.
- 计算了各种氧气空位配置和电荷状态的形成能量.
主要成果:
- 证明平面空隙在富含氧气的条件下表现出非常低的形成能量 (0.54 eV),与平面空隙 (4.0 eV) 形成鲜明对比.
- 证明平面空隙可以将铁电极化在[公式:见文本]中减少一个数量级以上.
- 确定了由这些平面氧气空缺引起的约72 Å的极化死层.
结论:
- 平面氧气空缺,特别是[公式:参见文本]电荷状态,是极化疲劳和铁电中印记的可能原因.
- 极化显著减少和死亡层的形成强调了这些缺陷在设备性能中的关键作用.
- 对局部Ti-O位移的微观分析为这些观察到的现象背后的机制提供了基本的见解.
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