Collaborative Research: Spin Correlations and Spin-Orbit Effects in New Quantum Materials

非技术总结该奖项支持俄亥俄州大学和佛罗里达大学的理论小组之间开展的合作研究和教育活动，与阿根廷和巴西的科学家密切合作，以联合收割机技术和专业知识相结合，解决材料研究中的重要和热门问题。 该项目将侧重于探索材料的电子特性，其中电子的自旋自由度受到其空间（轨道）运动的强烈影响。 自旋和轨道自由度的耦合是最近重新发现的现象，已被观察到影响金属，半导体和绝缘体中的许多性质，并且可以通过施加电场来增强。 将开展的研究旨在提供一个广泛适用的描述自旋轨道相互作用如何在不同的外场和微观环境下与排斥电子-电子相互作用竞争。 本说明书将适用于装饰或嵌入石墨烯（由碳原子制成的一个原子厚的二维材料），其他二维单晶和三维材料，其中电子激发的能量与它们的动量成线性比例。 该项目预计将提供对自旋轨道相互作用后果的基本见解，并促进对材料的理解，以更好地进行实验表征，并最终在磁性，自旋敏感电子学和量子信息处理中应用器件。 该项目团队还计划在其不同地点开展一些教育活动，包括在美国和拉丁美洲培训初级研究人员，以及外展工作，使作家生产从事书籍，为一般K-12观众的主题有关的研究。技术总结这一奖项将支持理论研究和教育活动，旨在实现一个基本的理解自旋-轨道相互作用及其与最近发现的材料中的库仑排斥的竞争，包括石墨烯及其衍生物，二维二硫属化物和Kagome晶体，三维狄拉克半金属，以及它们的异质结构。 除了它们迷人的和有点奇特的物理特性外，这些材料还承诺了各种令人兴奋的技术应用，从磁学和自旋电子学到新的碳基设备，甚至量子信息处理。项目团队计划采用并进一步开发适当的理论技术，包括数值重整化群，密度矩阵重整化群，连续和紧束缚散射矩阵方法，以及感兴趣系统的低能有效哈密顿量的场论表示。这些方法在处理强相关的问题方面是经过验证和可靠的，它们的互补性使合作具有独特的优势。 该研究小组由俄亥俄州大学和佛罗里达大学的理论小组组成，与阿根廷和巴西的科学家密切合作，将寻求推进技术，以扩大其适用范围，特别是与时间相关和非平衡现象有关的技术。 物质相之间的竞争，以及通过外部探针对其进行控制和修改，是需要研究的两个主要问题。一个特别的重点将是理解和指导实验的发展，与阐明的作用，内在的量子对称性在外部电磁场和应变场的存在下发挥的目标。 该项目团队还计划在其不同地点开展一些教育活动，包括在美国和拉丁美洲培训初级研究人员，以及开展外联工作，让作家为普通K-12观众制作与研究相关主题的引人入胜的书籍。

NON-TECHNICAL SUMMARYThis award supports collaborative research and educational activities carried out among theory groups at Ohio University and the University of Florida, working in close connection with scientists in Argentina and Brazil, to combine techniques and expertise and tackle important and topical problems in materials research. The project will focus on exploring electronic properties of materials where the electron's spin degree of freedom is strongly affected by their spatial (orbital) motion. The coupling of spin and orbital degrees of freedom is a recently rediscovered phenomenon that has been observed to impact a number of properties in metals, semiconductors, and insulators, and can be enhanced by applied electric fields. The research to be carried out is designed to provide a widely applicable description of how spin-orbit interactions compete with repulsive electron-electron interactions under different external fields and microscopic environments. This description will be applied to decorated or intercalated graphene (a two-dimensional material made of carbon atoms that is one atom thick), other two-dimensional single crystals, and three-dimensional materials in which the energy of the electronic excitations is linearly proportional to their momentum. The project is expected to provide fundamental insights into the consequences of spin-orbit interactions as well as to advance the understanding of materials for better experimental characterization and eventual device applications in magnetism, spin-sensitive electronics, and quantum information processing. The project team also plans a number of educational activities across its different sites, including the training of junior researchers in the US and Latin America, as well as outreach efforts that bring in writers to produce engaging books for a general K-12 audience on topics related to the research.TECHNICAL SUMMARYThis award will support theoretical research and educational activities aimed at achieving a fundamental understanding of spin-orbit interactions and their competition with Coulomb repulsion in recently discovered materials that include graphene and its derivatives, two-dimensional dichalcogenides and Kagome crystals, three-dimensional Dirac semimetals, and their heterostructures. In addition to their fascinating and somewhat exotic physical properties, these materials promise a variety of exciting technological applications, from magnetics and spintronics to new carbon-based devices, and even quantum information processing. The project team plans to employ and further develop appropriate theoretical techniques, including the numerical renormalization group, the density-matrix renormalization group, and continuous and tight-binding scattering-matrix approaches, as well as field-theoretical representations of low-energy effective Hamiltonians for the systems of interest. These approaches are proven and reliable in treating strongly correlated problems, and their complementarity gives the collaboration a unique advantage. The research team consisting of theory groups at Ohio University and the University of Florida, working in close collaboration with scientists in Argentina and Brazil, will seek to advance the techniques to enhance their range of applicability, especially in connection with time-dependent and non-equilibrium phenomena. Competition between phases of matter, and their control and modification through external probes, are the two main issues to be investigated. A particular focus will be on understanding and guiding experimental developments, with the goal of elucidating the role that intrinsic quantum symmetries play in the presence of external electromagnetic and strain fields. The project team also plans a number of educational activities across its different sites, including the training of junior researchers in the US and Latin America, as well as outreach efforts that bring in writers to produce engaging books for a general K-12 audience on topics related to the research.