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属性的区域的材料中，分隔这些区域的界面不仅影响整体材料特性，而且通常具有周围区域不存在的不寻常的物理属性。该项目研究了一种独特的二维材料中的界面，该材料由具有不同空间间隔的正负电荷的区域组成。了解这些接口的行为为使用具有大存储密度和超低功耗的高速逻辑和存储设备实现更快的计算以及探索可动态修改功能的下一代设备奠定了基础以适应不同的需求和应用。教育和外展活动是该项目的一个组成部分。除了为学生提供研究培训外，该项目还涉及开发融入本科物理课程的课堂演示和实验。首席研究员为当地中学生和高中生举办为期一周的年度科学营，并通过普尔曼市公园和娱乐部门提供。首席研究员还与当地组织合作，将开发的活动融入向公众开放的科学展览和科学博览会中。技术摘要：二维硒化铟是一种独特的铁电材料，其极化通过共价键维持，并具有相互关联的面外和面内极化。强共价键导致高度稳定的铁电性，其持续低至单层极限。互连的面外和面内极化允许使用局部电场来定义和操纵带电畴壁。这些畴壁具有独特的晶格结构，预计将表现出许多有趣和新颖的特性。该项目旨在发展畴壁特性的基础知识，具体目标是了解局部极化、晶格结构和电荷载流子之间复杂的耦合如何影响畴壁电子和声子特性。实验工作利用先进的电子显微镜和多功能扫描探针显微镜技术，例如尖端增强拉曼光谱和具有高空间和时间分辨率的各种基于原子力显微镜的测量，来探测各个畴壁中的局部特性。作为这些实验研究的补充，密度泛函理论计算用于确定晶格、电子和声子结构，以及载流子传输特性和畴壁动力学。实验和理论研究之间的相关性实现了机械见解，并为在电子应用中开发独特的畴壁特性提供了基本基础。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

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