Imaging and controlling moire interactions in two-dimensional semiconductor heterostructures

二维半导体异质结构中莫尔相互作用的成像和控制

• 批准号: 2003583
• 负责人: John Schaibley
• 金额: $ 49.74万
• 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: 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=2003583&HistoricalAwards=false
• 关键词: Imaging; controlling; moire; interactions; two

Two-dimensional (2D) materials are a single or few atoms thick. These ultra-thin materials exhibit a host of new electronic and other effects that have applications to new technologies, such as high speed computing, solar energy harvesting, and quantum-based technologies. Over the past decade, many 2D materials have been discovered, including 2D metals, semiconductors, and magnets. Furthermore, these 2D materials can be stacked together to realize properties that are enabled by the interactions between layers. These new properties enable electronic and optical devices, like transistors, solar cells and lasers. This research is focused on investigating multi-layer 2D material samples that use these interlayer interactions to realize new electronic and optical properties. In particular, by combining two different 2D semiconductors, the research team will explore states with trapped electrons. These trapped electrons can act as quantum light sources, which would help enable quantum communication devices that are secure against cyber-attacks. This research aligns with the NSF Big Idea of the Quantum Leap: Leading the Next Quantum Revolution by developing material systems that have the potential to enable these new quantum information technologies. Furthermore, the project strengthens the STEM workforce both directly and indirectly by training and mentoring graduate, undergraduate, and high school students through the proposed research, and by encouraging interest in STEM at the high school level in southern Arizona.The stacking of 2D materials in a vertical heterostructure leads to the formation of a long wavelength moiré pattern due to the lattice mismatch and relative orientation between the layers. This moiré pattern modulates the electronic and optical properties of the heterostructure leading to the confinement of electrons in one layer and holes in the other layer. These confined indirect excitons are known to serve as resources for quantum information science, and the PI will investigate how the novel physics of moiré confined excitons in 2D semiconductor heterostructures can be exploited to realize quantum devices with new functionalities. This project is focused on 2D semiconducting transition metal dichalcogenide heterostructures consisting of MoSe2 and WSe2 which form a type-II heterojunction. The research in this project advances knowledge of quantum materials physics by developing a comprehensive understanding of the role of twist angle and interlayer interactions in transition metal dichalcogenide heterostructures. In particular, the research has three aims: (1) Image the moiré potential in MoSe2/WSe2 heterostructures using scanning tunneling microscopy, (2) Directly measure spatially modulated moiré exciton emission using low-temperature scanning near field optical microscopy and (3) Control moiré interlayer excitons in 2D heterostructures. Lastly, modifying the interaction between layers and the potential landscape, allows for the tuning of the interlayer bandgap, the charging of trapped moiré excitons and the condensation of interlayer excitons in the moiré potential.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.

二维（2D）材料是单个或几个原子厚。这些超薄材料表现出许多新的电子和其他效应，可应用于新技术，如高速计算，太阳能收集和量子技术。在过去的十年中，已经发现了许多2D材料，包括2D金属，半导体和磁体。此外，这些2D材料可以堆叠在一起，以实现通过层间相互作用实现的特性。 这些新特性使电子和光学设备，如晶体管，太阳能电池和激光器。这项研究的重点是研究多层2D材料样品，利用这些层间相互作用来实现新的电子和光学特性。特别是，通过结合两种不同的2D半导体，研究团队将探索具有捕获电子的状态。这些被捕获的电子可以作为量子光源，这将有助于实现量子通信设备，使其免受网络攻击。这项研究符合NSF量子飞跃的大理念：通过开发有潜力实现这些新量子信息技术的材料系统来领导下一次量子革命。此外，该项目通过培训和指导研究生、本科生和高中生，直接和间接地加强STEM劳动力，并鼓励亚利桑那州南部高中对STEM的兴趣。垂直异质结构中二维材料的堆叠会由于晶格失配和材料之间的相对取向而导致长波长莫尔图案的形成。层次。 这种莫尔图案调制异质结构的电子和光学性质，导致电子限制在一层中，空穴限制在另一层中。 这些受限的间接激子被认为是量子信息科学的资源，PI将研究如何利用二维半导体异质结构中的莫尔限制激子的新物理来实现具有新功能的量子器件。 该项目的重点是由MoSe 2和WSe 2组成的2D半导体过渡金属二硫属化物异质结构，形成II型异质结。 该项目的研究通过全面了解过渡金属二硫属化物异质结构中扭曲角和层间相互作用的作用，推进了量子材料物理学的知识。 具体而言，本研究有三个目的：（1）使用扫描隧道显微镜对MoSe 2/WSe 2异质结构中的莫尔势进行成像，（2）使用低温扫描近场光学显微镜直接测量空间调制的莫尔激子发射，以及（3）控制二维异质结构中的莫尔层间激子。 最后，通过改变层间的相互作用和潜在的景观，可以调整层间带隙，对捕获的莫尔激子进行充电，以及在莫尔势中对层间激子进行凝聚。该奖项反映了NSF的法定使命，并通过使用基金会的知识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

Localized Interlayer Excitons in MoSe2-WSe2 Heterostructures without a Moiré Potential

无莫尔势的 MoSe2-WSe2 异质结构中的局域层间激子

• DOI: 10.48550/arxiv.2203.08052
• 发表时间: 2022
• 期刊: ArXivorg
• 作者: Mahdikhanysarvejahany, Fateme;Shanks, Daniel N.;Klein, Matthew;Wang, Qian;Koehler, Michael R.;Mandrus, David G.;Taniguchi, Takashi;Watanabe, Kenji;Monti, Oliver;LeRoy, Brian J.
• 通讯作者: LeRoy, Brian J.

Single-exciton trapping in an electrostatically defined two-dimensional semiconductor quantum dot

• DOI: 10.1103/physrevb.106.l201401
• 发表时间: 2022-06
• 期刊: Physical Review B
• 影响因子: 3.7
• 作者: Daniel N. Shanks;Fateme Mahdikhanysarvejahany;M. Koehler;D. Mandrus;T. Taniguchi;Kenji Watanabe

Temperature dependent moire trapping of interlayer excitons in MoSe2-WSe2 heterostructures

• DOI: 10.1038/s41699-021-00248-7
• 发表时间: 2021-07-21
• 期刊: NPJ 2D MATERIALS AND APPLICATIONS
• 影响因子: 9.7
• 作者: Mahdikhanysarvejahany, Fateme;Shanks, Daniel N.;Schaibley, John R.
• 通讯作者: Schaibley, John R.

Interlayer Exciton Diode and Transistor

• DOI: 10.1021/acs.nanolett.2c01905
• 发表时间: 2022-08-24
• 期刊: NANO LETTERS
• 影响因子: 10.8
• 作者: Shanks, Daniel N.;Mahdikhanysarvejahany, Fateme;Schaibley, John R.
• 通讯作者: Schaibley, John R.