Collaborative Research: Combined transport and scanning probe studies of transition metal dichalcogenide-based heterostructure devices

合作研究：基于过渡金属二硫属化物的异质结构器件的联合传输和扫描探针研究

• 批准号: 1607911
• 负责人: Brian LeRoy
• 金额: $ 26.5万
• 依托单位: University of Arizona
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-06-01 至 2020-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1607911&HistoricalAwards=false
• 关键词: Collaborative; Research; Combined; transport; scanning

Abstract:Non-Technical:Next generation electronics require advances in both materials and device designs. One promising direction is utilizing atomically thin materials because of their flexibility and high electron mobility. Graphene was the first such material identified in this new area of two-dimensional (2D) materials. Unfortunately, graphene is not a semiconductor, but a semimetal and is therefore not suitable for the digital logic circuits widely used today in electronics. Transition metal dichalcogenides are a family of 2D materials which share many of the promising aspects of graphene such as being atomically thin. In addition, they exhibit a wider variety of electronic and optoelectronic properties compared to graphene including many being semiconducting or metallic. This wide range of transition metal dichalcogenides allows one to select a material or a combination of materials best suited for a particular application. Indeed, by combining different 2D materials together in vertical heterostructures an even wider range of new device functionalities can be enabled. This collaborative research program will create new educational and research opportunities at both the University of Arizona, and the University of Texas at Austin. The program will strongly emphasize the training of graduate and undergraduate students from underserved groups, thus preparing them for industrial or academic careers. This workforce training, along with the expected research output, will boost the efforts to make our nation more competitive.Technical:The goal of this collaborative research program is to study layered two-dimensional transition metal dichalcogenide materials and heterostructures for device applications, using a combination of controlled heterostructure fabrication techniques, scanning probe microscopy, and electrical transport measurements. Similar to graphene, the most widely studied two-dimensional material, transition metal dichalcogenides represent a larger class of layered materials with varying electronic properties, from semiconducting to superconducting. The diverse set of electronic properties in these materials makes them suitable for applications ranging from transistors to chemical sensors or photodetectors. Key to an understanding of their fundamental electronic properties is the role of the disorder potential, interfaces, and edges in individual layers, and of the band and rotational alignment in heterostructures. Specifically, the proposed effort will (1) measure band-alignment in transition metal dichalcogenide based heterostructures, (2) realize heterostructures of two-dimensional materials with controlled rotational alignment, (3) explore the impact of rotational alignment on the electronic properties of two-dimensional material heterostructures, and using these ingredients (4) design and fabricate novel heterostructure tunneling devices. This program builds on the PIs existing collaborative research and recent preliminary data on the fabrication and characterization of these heterostructures. The outcomes of this research program will include uncovering fundamental electronic properties of transition metal dichalcogenide-based heterostructures, new methods to create heterostructures, and novel devices for future electronics applications.

翻译后摘要：非技术：下一代电子产品需要在材料和设备设计的进步。 一个有前途的方向是利用原子级薄的材料，因为它们的灵活性和高电子迁移率。 石墨烯是在二维（2D）材料这一新领域中发现的第一种此类材料。 不幸的是，石墨烯不是半导体，而是半金属，因此不适用于当今电子产品中广泛使用的数字逻辑电路。 过渡金属二硫属化物是一系列2D材料，它们具有石墨烯的许多有前途的方面，例如原子薄。 此外，与石墨烯相比，它们表现出更广泛的电子和光电特性，包括许多半导体或金属。 这种宽范围的过渡金属二硫属化物允许人们选择最适合于特定应用的材料或材料的组合。 事实上，通过将不同的2D材料在垂直异质结构中组合在一起，可以实现更广泛的新器件功能。 这项合作研究计划将在亚利桑那大学和德克萨斯大学奥斯汀分校创造新的教育和研究机会。 该计划将大力强调从服务不足的群体的研究生和本科生的培训，从而为他们的工业或学术生涯做好准备。这种劳动力培训，沿着预期的研究成果，将推动努力，使我们的国家更具竞争力。技术：这个合作研究计划的目标是研究分层的二维过渡金属二硫属化物材料和异质结构的设备应用，使用控制异质结构制造技术，扫描探针显微镜和电输运测量的组合。 类似于石墨烯，最广泛研究的二维材料，过渡金属二硫属化物代表了一个更大类别的分层材料，具有不同的电子特性，从半导体到超导。这些材料中的各种电子特性使其适用于从晶体管到化学传感器或光电探测器的应用。理解其基本电子性质的关键是无序势，界面和边缘在各个层中的作用，以及异质结构中的能带和旋转排列。 具体而言，所提出的努力将（1）测量过渡金属二硫属化物基异质结构中的能带对准，（2）实现具有受控旋转对准的二维材料的异质结构，（3）探索旋转对准对二维材料异质结构的电子性质的影响，并使用这些成分（4）设计和制造新型异质结构隧穿器件。 该计划建立在PI现有的合作研究和最近的初步数据，这些异质结构的制造和表征。 该研究计划的成果将包括揭示过渡金属二硫属化物基异质结构的基本电子特性，创建异质结构的新方法以及用于未来电子应用的新型器件。

项目成果

Probing the wave functions of correlated states in magic angle graphene

探讨魔角石墨烯中相关态的波函数

• DOI: 10.1103/physrevresearch.2.033181
• 发表时间: 2020
• 期刊: Physical Review Research
• 影响因子: 4.2
• 作者: Zhang, Zhiming;Myers, Rachel;Watanabe, Kenji;Taniguchi, Takashi;LeRoy, Brian J.
• 通讯作者: LeRoy, Brian J.

Flat bands in twisted bilayer transition metal dichalcogenides

• DOI: 10.1038/s41567-020-0958-x
• 发表时间: 2020-07-06
• 期刊: NATURE PHYSICS
• 影响因子: 19.6
• 作者: Zhang, Zhiming;Wang, Yimeng;LeRoy, Brian J.
• 通讯作者: LeRoy, Brian J.