Understanding Domain Walls in a Two-Dimensional Ferroelectric Material

了解二维铁电材料中的畴壁

• 批准号: 2004655
• 负责人: Yi Gu
• 金额: $ 47.78万
• 依托单位: Washington State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-07-01 至 2024-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2004655&HistoricalAwards=false
• 关键词: Understanding; Domain; Walls; Two; Dimensional

Nontechnical Summary:In materials that contain regions with different structures and properties, the interfaces that separate these regions not only influence the overall material characteristics, but also often feature unusual physical properties not present in the surrounding regions. This project investigates interfaces in a unique two-dimensional material consisting of regions characterized by different spatial separations of positive and negative electric charges. Knowledge of the behaviors of these interfaces lays the groundwork for realizing faster computing using high-speed logic and memory devices with large storage density and ultra-low power consumption, as well as for exploring next-generation devices whose functions can be modified on the fly to adapt to different demands and applications. Education and outreach activities are an integral part of this project. In addition to providing research training for students, this project involves the development of classroom demonstrations and experiments that are integrated into an undergraduate physics course. A week-long annual science camp for local middle and high school students is developed by the principal investigator and offered through the Parks and Recreation Department in the City of Pullman. The principal investigator also works with local organizations to integrate the developed activities into science exhibitions and science fairs that are open to the general public. Technical Summary:Two-dimensional indium selenide is a unique ferroelectric material, with the polarization sustained by covalent bonding and with interlinked out-of-plane and in-plane polarizations. The strong covalent bonding leads to highly robust ferroelectricity that persists down to the monolayer limit. The interlinked out-of-plane and in-plane polarizations allow for defining and manipulating charged domain walls using a local electric field. These domain walls have distinctive lattice structures and are expected to exhibit many interesting and novel characteristics. This project aims to develop a fundamental knowledge of the domain wall properties, with the specific objective to understand how the intricate coupling between the local polarization, lattice structure, and charge carriers affects the domain wall electronic and phonon properties. The experimental efforts utilize advanced electron microscopy and multi-functional scanning probe microscopy techniques, such as tip-enhanced Raman spectroscopy and various atomic force microscopy-based measurements with high spatial and temporal resolutions, to probe local properties in individual domain walls. Complementing these experimental investigations, density-functional-theory calculations are used to determine the crystal lattices, electronic and phonon structures, as well as charge carrier transport properties and dynamics in domain walls. The correlation between experimental and theoretical studies enables mechanistic insights and provides a fundamental basis for exploiting unique domain wall properties in electronic applications.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

非技术摘要：在包含具有不同结构和特性区域的材料中，分离这些区域的界面不仅会影响整体材料特征，而且通常具有周围地区不存在的异常物理特性。该项目研究了独特的二维材料中的界面，该材料由以正空和负电荷的不同空间分离为特征的区域组成。了解这些接口的行为的知识为使用具有较大的存储密度和超低功耗的高速逻辑和内存设备以及探索可以随机修改的下一代设备探索以适应不同需求和应用程序的函数。教育和外展活动是该项目不可或缺的一部分。除了为学生提供研究培训外，该项目还涉及将课堂演示和实验纳入本科物理课程的发展。首席调查员开发了为期一周的当地中学和高中生的年度科学训练营，并通过普尔曼市的公园和娱乐部门提供。首席研究人员还与当地组织合作，将开发的活动纳入向公众开放的科学展览和科学展览会。技术摘要：二维硒化物是一种独特的铁电材料，其极化是通过共价键合，并且相互链接的平面外和平面极化。强大的共价键合导致高度鲁棒的铁电性，持续到单层极限。相互链接的平面外和平面极化允许使用局部电场来定义和操纵带电的域壁。这些域壁具有独特的晶格结构，并有望表现出许多有趣且新颖的特征。该项目旨在开发域壁性质的基本知识，并具有特定的目标，以了解局部极化，晶格结构和荷载载流子之间的复杂耦合如何影响域壁电子和声子特性。实验工作利用了先进的电子显微镜和多功能扫描探针显微镜技术，例如具有高空间和时间分辨率的基于尖端增强的拉曼光谱和各种原子力显微镜测量，以探测各个域壁中局部特性。与这些实验研究相辅相成，使用密度功能理论的计算用于确定晶体壁中的晶体晶格，电子和声子结构以及电荷载体传输性能和域壁中的动力学。实验研究和理论研究之间的相关性使机械洞察力可以利用电子应用中独特的域壁性能。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的智力优点和更广泛的影响审查标准通过评估来进行评估的。

项目成果

Selective Plasmon-Induced Oxidation of 4-Aminothiophenol on Silver Nanoparticles

银纳米颗粒上 4-氨基苯硫酚的选择性等离子体诱导氧化

• DOI: 10.1021/acs.jpcc.3c01204
• 发表时间: 2023
• 期刊: The Journal of Physical Chemistry C
• 作者: Mantilla, Alexander B.;Matthews, Bethany E.;Gu, Yi;El-Khoury, Patrick Z.
• 通讯作者: El-Khoury, Patrick Z.

Multipolar Raman Scattering vs Interfacial Nanochemistry: Case of 4-Mercaptopyridine on Gold.

• DOI: 10.1021/jacs.2c10132
• 发表时间: 2022-11-16
• 期刊: JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
• 影响因子: 15
• 作者: Mantilla, Alexander B. C.;Wang, Chih-Feng;Gu, Yi;Schultz, Zachary D.;El-Khoury, Patrick Z.
• 通讯作者: El-Khoury, Patrick Z.

van der Waals ferroelectrics: Progress and an outlook for future research directions

• DOI: 10.1063/5.0117355
• 发表时间: 2022-10
• 期刊: Journal of Applied Physics
• 影响因子: 3.2
• 作者: J. Parker;Y. Gu