US Ireland Research and Development Partnership: Spin and valley interactions in intrinsic and magnetic two dimensional transition metal dichalcogenides for novel devices

美国爱尔兰研究与开发合作伙伴关系：新型器件的本征和磁性二维过渡金属二硫属化物中的自旋和谷相互作用

• 批准号: 1608389
• 负责人: Richard Lehman
• 金额: $ 36万
• 依托单位: Rutgers University New Brunswick
• 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: 2016-08-15 至 2021-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1608389&HistoricalAwards=false
• 关键词: US; Ireland; Research; Development; Partnership

Two dimensional transition metal dichalcogenides (2D TMDs) are the ideal platform for exploration of fundamental spin and valley interactions that will form the foundation of spintronic and valleytronic devices. In this project, researchers from the United States, Republic of Ireland (ROI), and Northern Ireland (NI) propose to study fundamental properties, such as phase and spin coherences, inter-valley scattering, and magnetism in intrinsic and magnetically doped 2D TMDs. Each PI will be supported by their respective funding agencies through the US Ireland R & D Partnership Program. The Research Team is interdisciplinary with complementary expertise. The NI group will carry out multi-scale modeling using state-of-the-art theoretical methods to predict new properties as well as provide fundamental understanding of the experimental work. The ROI group will provide multi-scale characterization and develop new scanning transmission electron microscopy methods to simultaneously obtain information about atomic and magnetic structures. The US group will investigate new synthesis methods to obtain magnetic 2D materials and perform quantum transport measurements to elucidate fundamental spin and inter-valley scattering mechanisms. The collaborative research will lead to realization of synergies through formation of an interdisciplinary team who will work on spin and valley physics in 2D materials to enable exciting scientific discoveries. The educational and training activities of the proposed project will complement the scientific impact of the proposed project. The graduate students from the US, Ireland, and Northern Ireland will benefit from the scientific and educational components of the program. This collaboration will result in developing highly engaged, globally networked graduate students with interdisciplinary knowledge experienced in international and national laboratory environments. The students will benefit from international exchanges by developing new skills beyond the expertise of their core doctoral thesis topics. Additionally, focused outreach activities will involve engaging high school students as well as middle and high school teachers to be familiarized with materials science as well as engaging public by organizing laboratory tours, designing hands-on demonstrations, and issuing timely press releases.The main goal of this proposal is to provide new insights in: (i) fundamental interactions of spin and valley with magnetic impurities in the very dilute (i.e. intrinsic) or weak magnetic ordering regime; and (ii) ferromagnetism in 2D semiconductors in the high magnetic ordering regime and its influence on spin polarization and coherence. The new knowledge obtained from this project will be complementary in realizing future spintronics and valleytronics devices based on 2D TMDs. In addition, electrical doping remains an unresolved question in 2D semiconductors and it is expected the outcome of this research will address key fundamental questions regarding thermodynamic concentration limit and influence of impurities on electronic and magnetic properties. These properties will be investigated by quantum transport and Hall Effect measurements to obtain information about weak localization for the non-magnetic materials. Information about spin-polarized transport in magnetic samples will be obtained using magneto-resistance measurements with in-plane magnetic fields. It is expected that the research will generate the foundation of new fundamental knowledge and investigate the feasibility of experimentally realizing 2D magnetic TMDs for fabrication of spintronic and valleytronic devices. This US-Ireland partnership will provide a framework to collaborate theoretically and experimentally for realizing new 2D materials properties and thier potential synergies for device applications.

二维过渡金属二硫化物（2D TMD）是探索基本自旋和谷相互作用的理想平台，这将构成自旋电子和谷电子器件的基础。在该项目中，来自美国、爱尔兰共和国 (ROI) 和北爱尔兰 (NI) 的研究人员提议研究本征和磁掺杂二维 TMD 的基本特性，例如相位和自旋相干性、谷间散射以及磁性。 每个 PI 将通过美国爱尔兰研发合作伙伴计划获得各自资助机构的支持。 研究团队是跨学科的，具有互补的专业知识。 NI 团队将使用最先进的理论方法进行多尺度建模，以预测新特性并提供对实验工作的基本理解。 ROI小组将提供多尺度表征并开发新的扫描透射电子显微镜方法，以同时获取有关原子和磁性结构的信息。 美国研究小组将研究新的合成方法以获得磁性二维材料并进行量子输运测量以阐明基本的自旋和谷间散射机制。 此次合作研究将通过组建一个跨学科团队来实现协同效应，该团队将致力于二维材料中的自旋和谷物理研究，以实现令人兴奋的科学发现。 拟议项目的教育和培训活动将补充拟议项目的科学影响。 来自美国、爱尔兰和北爱尔兰的研究生将受益于该项目的科学和教育部分。 此次合作将培养高度参与、全球网络化的研究生，他们拥有在国际和国家实验室环境中经验丰富的跨学科知识。 学生将通过发展核心博士论文主题专业知识之外的新技能，从国际交流中受益。 此外，重点推广活动将包括让高中生以及初中和高中教师熟悉材料科学，并通过组织实验室参观、设计实践演示和及时发布新闻稿来吸引公众。该提案的主要目标是提供以下方面的新见解：(i) 在极稀（即本征）或弱磁序中自旋和谷与磁性杂质的基本相互作用 政权； (ii) 高磁有序状态下二维半导体的铁磁性及其对自旋极化和相干性的影响。 从该项目中获得的新知识将在实现基于 2D TMD 的未来自旋电子学和谷电子学器件方面起到补充作用。 此外，电掺杂在二维半导体中仍然是一个未解决的问题，预计这项研究的结果将解决有关热力学浓度限制以及杂质对电子和磁性能影响的关键基本问题。 这些特性将通过量子输运和霍尔效应测量进行研究，以获得有关非磁性材料弱局域化的信息。 有关磁性样品中自旋极化输运的信息将通过平面内磁场的磁阻测量来获得。 预计该研究将为新的基础知识奠定基础，并研究通过实验实现 2D 磁性 TMD 用于制造自旋电子和谷电子器件的可行性。 美国与爱尔兰的这一合作伙伴关系将为理论和实验合作提供一个框架，以实现新的二维材料特性及其在设备应用中的潜在协同效应。