Materials World Network: New Insights into Ferroelectric Domain Walls: Extended Nanoscale Structure, Bloch-Like and Neel-Like Character, and Spatially Resolved Dynamics

材料世界网络：对铁电畴壁的新见解：扩展的纳米级结构、类布洛赫和类尼尔特征以及空间分辨动力学

• 批准号: 0908718
• 负责人: Venkatraman Gopalan
• 金额: $ 57万
• 依托单位: Pennsylvania State Univ University Park
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-01 至 2013-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0908718&HistoricalAwards=false
• 关键词: Materials; World; Network; New; Insights

This MWN research focuses on new insights into the fundamental nature of ferroelectric domain walls developed by this joint US/Ukraine team over the past two years. In particular, the team leverages the comprehensive theory, simulation and advanced experimental framework they have developed for quantitative piezoelectric force microscopy (PFM). Using this framework, they have discovered unexpected broadening of ferroelectric domain walls over tens of nanometers. Analytical theory and phase field modeling, predicts that even a few nanometers of broadening can dramatically change the macroscale properties such as threshold fields for wall motion, by many orders of magnitude. The team predicts unusual magnetic-like domain walls in ferroelectrics. Such walls can be engineered to be extremely broad, (100's nm), and their dynamical properties under electric fields, and hence their impact on macroscale properties are presently unexplored. Using Scanning Spectroscopy Piezoelectric Force Microscopy (SSPFM), and optical second harmonic generation-near field scanning optical microscopy (SHG-NSOM), the team is exploring this mysterious new world of domain walls. Broadly speaking, the US team (Penn State and Oak Ridge National Labs) focuses on the experimental and phase-field simulations of such ferroelectric walls, while the Ukranian team (National Academy of Sciences, Ukraine) is developing the theoretical framework.The development of quantitative PFM and SHG-NSOM imaging techniques that combine theory, numerical simulations and cutting-edge experimental techniques are expected to have a much broader impact that extends beyond ferroelectrics, to other fields of materials science, chemistry and life sciences. This US/Ukranian team is an excellent example of a genuine international collaboration that started rather spontaneously a few years ago between the PIs, and has been very productive. This proposal will provide funds to energize and sustain this spontaneous effort by supporting undergraduate and graduate students to work and collaborate in a global context, support extended visits across the Atlantic by PIs and students alike, further interactions between a university (Penn State), a national lab (Oak-Ridge National Lab) and a national academy (NAS-Ukraine), support organization of an annual international workshop on Piezoelectric Force Microscopy and summer workshops in nonlinear optical microscopy, and provide research opportunities for women and underrepresented groups.This MWN award is co-funded by DMR-EPM, DMR-OSP, and OISE Eurasia Region.

这项MWN研究重点是对过去两年美国/乌克兰团队开发的铁电域墙的基本性质的新见解。特别是，该团队利用他们为定量压电显微镜（PFM）开发的综合理论，模拟和高级实验框架。 使用此框架，他们发现了在数十纳米上的铁电域壁的意外扩展。 分析理论和相位场建模，可以预测，即使是拓宽的一些纳米也可以大大改变宏观尺度的特性，例如壁运动的阈值字段。 该团队预测铁电的异常磁性域壁。这样的墙可以设计为非常宽（100 nm），并且它们在电场下的动力学性质，因此目前尚未探索它们对宏观属性的影响。使用扫描光谱电压电压显微镜（SSPFM）和光学的第二谐波生成田扫描光学显微镜（SHG-NSOM），该团队正在探索这个神秘的域名域墙壁。从广义上讲，美国团队（宾夕法尼亚州立大学和橡树岭国家实验室）着重于此类铁电墙的实验和相位模拟，而乌克兰尼亚团队（乌克兰国家科学院，国家科学院，乌克兰）正在发展理论框架。超越铁电的更广泛的影响，到其他材料科学，化学和生命科学领域。 这支美国/乌克兰队是一个真正的国际合作的一个很好的例子，该合作是几年前在PIS之间自发开始的，并且非常有生产力。 This proposal will provide funds to energize and sustain this spontaneous effort by supporting undergraduate and graduate students to work and collaborate in a global context, support extended visits across the Atlantic by PIs and students alike, further interactions between a university (Penn State), a national lab (Oak-Ridge National Lab) and a national academy (NAS-Ukraine), support organization of an annual international workshop on Piezoelectric Force Microscopy and summer非线性光学显微镜的研讨会，并为妇女和代表性不足的组提供研究机会。该MWN奖由DMR-EPM，DMR-SOPS和OISE EURASIA地区共同资助。