Layered Electrostatic Heterostructures for Electronics and Photonics

用于电子和光子学的层状静电异质结构

• 批准号: 1610861
• 负责人: Scott Warren
• 金额: $ 45.64万
• 依托单位: University of North Carolina at Chapel Hill
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-07-01 至 2020-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1610861&HistoricalAwards=false
• 关键词: Layered; Electrostatic; Heterostructures; Electronics; Photonics

Non-technical Description: When a material's size is reduced to atomic dimensions, material properties become profoundly altered, and new opportunities emerge for discovering useful phenomena. An important example of this occurs in two dimensional materials, which are sheet-like objects that are just a few atoms thick. This project addresses fundamental challenges in understanding the behavior of these materials when the two dimensional materials are stacked on top of each other to build a multi-layered composite. The materials synthesized in this project are useful for information technology and energy conversion and storage. The research in this project is integrated into many aspects of outreach and education. The students who work on this project are exposed to advanced challenges in materials synthesis and characterization. This project also engages the broader public through several activities, including outreach to high-school students through demonstrations that use art supplies such as graphite, clay, and mica - all of which are built from two dimensional materials - to engage students in scientific inquiry.Technical Description: Recent observations of emergent properties in few-flake stacks of graphene, boron nitride, and dichalcogenides, termed van der Waals heterostructures, have generated immense interest because of their remarkable electronic, optical, chemical, and mechanical properties. All of the studied van der Waals heterostructures are held together primarily by weak van der Waals interactions, highlighting an opportunity to design and understand multilayered materials that are held together by stronger forces, especially electrostatic forces. The primary research goal is to build model heterostructures and understand the principles that relate their structure to their electronic and photonic properties. This project combines experimental and theoretical approaches, including microspectroscopy to assess the optical properties, conductivity measurements to assess electronic coupling and charge transfer, and photoemission spectroscopy coupled with density functional theory calculations to assess band structure. Ultimately, an understanding of the structure-property relationships in these heterostructures can provide an important framework for designing the optoelectronic properties of these new materials.

非技术描述：当材料的尺寸缩小到原子尺寸时，材料的性质会发生深刻的变化，并出现发现有用现象的新机会。这方面的一个重要例子发生在二维材料中，二维材料是只有几个原子厚的片状物体。该项目解决了理解这些材料的行为时，二维材料堆叠在彼此之上，以建立一个多层复合材料的基本挑战。该项目合成的材料可用于信息技术和能量转换与储存。该项目的研究被纳入外联和教育的许多方面。从事该项目的学生将面临材料合成和表征方面的高级挑战。该项目还通过几项活动吸引了更广泛的公众，包括通过使用石墨、粘土和云母等艺术用品（所有这些都是由二维材料制成的）进行演示来吸引高中生参与科学探究。技术描述：最近在石墨烯、氮化硼和二硫属化物的少量薄片堆叠中观察到的涌现特性，称为货车德瓦尔斯异质结构，由于其显著的电子、光学、化学和机械性能而引起了人们极大的兴趣。所有研究的货车德瓦尔斯异质结构主要通过弱货车德瓦尔斯相互作用结合在一起，突出了设计和理解通过更强的力，特别是静电力结合在一起的多层材料的机会。主要研究目标是建立异质结构模型，并了解其结构与电子和光子特性之间的关系。该项目结合了实验和理论方法，包括显微光谱学来评估光学性质，电导率测量来评估电子耦合和电荷转移，以及光电发射光谱与密度泛函理论计算相结合来评估能带结构。最终，这些异质结构中的结构-性质关系的理解可以为设计这些新材料的光电性能提供重要的框架。