Quantum Phenomena in Solids

技术综述：该奖项支持固体中量子关联现象的理论研究和教育。长期目标是开发具有目前没有的有用功能的新材料和结构，并扩展基本科学框架，以在新的制度和新的阶段理解物质。研究推力跨越了大宗材料和异质结构。在前者中，PI将研究(1)挫折和波动，及其后果和应用；(2)磁电耦合；(3)轨道波动和有序。在异质结领域，PI将考虑相关电子材料之间的界面，这在实验上正成为一个非常令人兴奋的课题。PI旨在解决量子磁体、多铁性、自旋轨道耦合材料和更复杂的Mott绝缘体等实验中提出的关键悬而未决的问题。主题的广度是这个研究项目的一项资产；通过在更广泛的背景下查看一种材料或结构，PI旨在获得对可能涉及的非常多影响的相对重要性的洞察。理论技术呢？例如统计力学、场论、重整化群、数值方法、约束计数？它将被用来研究相互竞争的相互作用和涨落，也广泛适用于所有这些问题。在过去的5年里，通过脉冲激光沉积在过渡金属氧化物之间生长高质量的原子精密界面方面的进展是显著的。这是一个非常令人兴奋的新场所，用于研究关联现象，并最终应用于从具有附加功能的关联材料构建半导体风格的异质结构。PI将开展基础研究，旨在阐明在这些界面上发生的新物理以及它们与半导体异质结构的不同之处。该奖项支持凝聚态理论前沿领域的研究生和博士后教育。将开发新的课程材料，将该领域的兴奋传达给新学生。非技术总结：该奖项支持理论研究和教育，以激励和解释实验和材料的性质。PI将专注于他认为最有可能导致革命性技术影响的特定领域。这些领域也推动了基础科学的发展。实验揭示了具有成为磁体所需成分的材料，但不显示出磁性。在原子的尺度上，相互作用之间存在着一种竞争，这种相互作用有利于对齐基本的磁性构件和原子的几何排列。这挫败了磁性秩序的倾向。实验继续提供更多的例子，如矿物Herbertsmithite和Volborthite，使测试理论想法成为可能，即失败的磁性将产生新的物质状态。PI还将研究电子电荷和磁性紧密耦合的材料。多铁性材料是一类典型的材料，它们同时表现出磁性和类似磁性的电荷。PI还将研究一类新的绝缘材料(称为拓扑绝缘体)中的自旋和电荷耦合产生的现象，这种材料具有大量涉及电子运动产生的磁性新现象的可能性。最近的一项实验进展使两种不同的氧化物材料能够连接起来，类似于构成现代电子基础的半导体之间的界面。在这种情况下，氧化物材料具有不寻常的性质，这些性质源于电子之间的强烈相互作用。这样创造的界面丰富，有可能产生新的现象和新的材料性能，可能会产生技术上的影响。PI将使用复杂的理论工具来理解最近的实验并预测新的现象。需要先进量子力学的基本工具来理解这些系统上的实验，并通过预测来阐明新的可能性，以激励进一步的实验。这项工作有助于为未来的电子和信息技术奠定基础。该奖项有助于为研究生和博士后水平的学生提供优质的教育体验。

TECHNICAL SUMMARY:This award supports theoretical research and education on quantum correlation phenomena in solids. The long-term goals are to develop new materials and structures with useful functionality not currently available, and to extend the basic scientific framework to understand matter in new regimes and new phases. The research thrusts span bulk materials and heterostructures. In the former, the PI will study (1) frustration and fluctuations, and their consequences and applications; (2) magneto-electric coupling; and (3) orbital fluctuations and ordering. In the heterostructure area, the PI will consider interfaces between correlated electron materials, which are becoming a very exciting subject experimentally. The PI aims to address key outstanding questions raised by experiments in quantum magnets, multiferroics, spin-orbit coupled materials, and more complex Mott insulators. The breadth of topics is an asset to this research program; by viewing one material or structure in a broader context, the PI aims to obtain insights into the relative importance of the very many effects that might be involved. The theoretical techniques ? e.g. statistical mechanics, field theory, renormalization group, numerical methods, constraint counting ? which will be used to study competing interactions and fluctuations are also widely applicable across all these problems.Advances in the past 5 years in growing high quality atomic precision interfaces between transition metal oxides by pulsed laser deposition are remarkable. This is an extremely exciting new venue for correlation phenomena and also eventual applications building semiconductor-style heterostructures from correlated materials with their additional functionalities. The PI will carry out fundamental research aimed at elucidating the new physics occuring at these interfaces and how they differ from semiconductor heterostructures.This award supports the education of graduate students and postdocs in forefront areas of condensed matter theory. New course materials will be developed to convey the excitement of the fields to new students. NON-TECHNICAL SUMMARY:This award supports theoretical research and education to motivate and explain experiments and properties of materials. The PI will focus on particular areas which he believes are those most likely to lead to revolutionary technological impacts. These areas also advance fundamental science. Experiments reveal materials that have the necessary ingredients to become magnets, but do not exhibit magnetism. On the scale of atoms, there is a competition between the interactions that would favor aligning the fundamental building blocks of magnetism and the geometrical arrangements of the atoms. This frustrates the tendency to magnetic order. Experiments continue to deliver more examples, like the minerals Herbertsmithite and Volborthite, enabling the test of theoretical ideas that new states of matter will arise from failed magnetism. The PI will also study materials where electron charge and magnetism are closely coupled. Multiferroics are an example class of materials; they simultaneously exhibit magnetism and the electric charge analog of magnetism. The PI will also study phenomena that arise from the coupling of spin and charge in a new class of insulating materials, called topological insulators, that are rich with possibilities for new phenomena involving magnetism that arise from the motion of electrons. A recent experimental advance enables the joining of two different oxide materials, analogous to the interfaces between semiconductors that form the basis of modern electronics. In this case the oxide materials have unusual properties that arise from strong interactions between electrons. The interfaces so created are rich with the potential for new phenomena and new materials properties that may have technological impact. The PI will use sophisticated theoretical tools to understand recent experiments and predict new phenomena. The fundamental tools of advanced quantum mechanics are needed to understand experiments on these systems and to illuminate new possibilities with predictions that motivate further experiment. This work contributes to the foundations of future electronic and information technologies. This award helps provide a quality educational experience for students at the graduate and postdoctoral level.