在中心对称氧化物中诱导巨型压电
D-S Park1,2, M Hadad2, L M Riemer1
1Group for Ferroelectrics and Functional Oxides, Swiss Federal Institute of Technology-EPFL, 1015 Lausanne, Switzerland.
Science (New York, N.Y.)
|February 10, 2022
概括
研究人员通过用电场重新安排氧气空隙,在通常非压电中心对称材料中诱导了显著的压电效应. 这一突破使得新型环保压电材料的设计成为可能.
科学领域:
- 材料科学
- 固态物理
- 晶体学
背景情况:
- 压电材料对于各种电子应用是必不可少的.
- 一个非中心对称的晶体结构是压电的基本前提.
- 由于结构上的局限性,开发新的压电材料具有挑战性.
研究的目的:
- 克服传统压电材料的结构限制.
- 在中心对称材料中诱导压电效应.
- 探索产生大型压电反应的新方法.
主要方法:
- 诱导中心对称材料中氧气空位的电场驱动的重新排列.
- 使用加多添加的CeO2-x薄膜,具有立方结构.
- 在毫赫兹频率下测量压电应变系数 (d33).
主要成果:
- 在中心对称的加多化CeO2-x膜中产生了非常大的压电反应 (d33~200,000 pm/V).
- 观察到的压电效应比最先进的基材料大两倍.
- 通过打破晶体对称性来实现可持续的压电效应.
结论:
- 电场诱导的氧气空位重新排列可以在中心对称材料中产生显著的压电.
- 这种方法为设计高性能,环保的压电材料提供了新的途径.
- 这些发现挑战了长期存在的非中心对称的先决条件.
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