铁电尺寸对域墙的静态和动态的影响
Somnath Kale1, Adrian Petraru2, Hermann Kohlstedt2
1Department of Physical Sciences, Indian Institute of Science Education and Research Berhampur, Berhampur, 760010, India.
Small (Weinheim an der Bergstrasse, Germany)
|September 4, 2023
概括
铁电酸薄膜中的域壁行为随着厚度的变化而变化,从2D过渡到准-1D. 这种厚度依赖的维度转移会影响纳米级铁电器件的功能.
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
- 纳米技术 纳米技术
背景情况:
- 铁电材料中的域壁显著影响纳米尺度特性和设备性能.
- 之前的研究已经探索了铁电纳米结构的尺寸效应,但厚度减小对域壁缩放的影响在很大程度上仍未得到研究.
研究的目的:
- 为了研究薄膜厚度对表轴酸 (BaTiO3) 薄膜中的域壁的缩放行为和维度的影响.
- 了解厚度缩小如何影响关键缩放普遍性,包括动态爬行和静态粗指数.
主要方法:
- 利用压响应力显微镜 (PFM) 探测域壁动态和静态特性.
- 通过测量静态粗度和动态爬行指数,在各种薄膜厚度 (2-90 nm) 中分析了缩放行为.
- 采用结构分析和基质诱导的菌株修饰来研究潜在的机制.
主要成果:
- 在10-25纳米厚度的BaTiO3薄膜中,证明了域壁维度从二维 (2D) 过渡到准一维 (准-1D).
- 观察到的静态粗度指数 (0.34到0.28) 和动态爬行指数 (0.54到0.22) 的变化与这个维度过渡相关.
- 在随机结合普遍性范式中使用有效维度计算验证了跨维度过渡.
结论:
- 薄膜厚度是控制铁电纳米结构域壁维度和缩放行为的关键因素.
- 压缩应变和应变双极相互作用被确定为驱动观察到的跨维度过渡的关键因素.
- 这些发现为纳米级铁电提供了新的见解,并为设计先进的铁电纳米设备提供了基础.
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