Quantum soliton hydrodynamics in magnetic insulators

非技术总结该奖项支持开发一种类似于流体力学的描述磁性材料中自旋输运的方法的理论研究和教育。除了携带电荷，在物质中运动的电子还带有一个被称为自旋的微小磁矩。对这些磁矩的操纵使新型电子设备成为可能，这些设备除了利用电荷外，还利用自旋。在某些情况下，可以通过类似于对流体的描述来实现对自旋的传输和许多自旋共同产生的磁性排列(织构)的描述。PI将开发一个理论框架来描述自旋织构如何在磁性材料中相互作用和流动。PI与加州大学洛杉矶分校的材料科学家和工程师的研究和合作将有助于开发和支持基于利用自旋织构的材料的记忆、逻辑和通信设备的概念。除了研究，PI还将继续参与加州大学洛杉矶分校加州纳米系统研究所赞助的一个成功的推广项目，该项目为洛杉矶统一学区公立学校的高中生带来纳米科学和纳米技术实验，以及理论解释和演示。PI还将为加州大学洛杉矶分校的本科生研究体验项目开发一个以凝聚态理论为中心的组成部分，在该项目中，本科生与教师导师以及其他教授、研究人员和研究生合作进行暑期研究项目。技术总结该奖项支持理论研究和教育，以发展与磁性绝缘体中拓扑孤子的波动和流动有关的真实空间拓扑流体动力学理论。磁系统中热流和自旋动力学的相互作用将自旋电子学领域的大部分兴趣转移到了自旋输运的集体形式上。重要的例子是拓扑自旋织构，如手性磁场壁和Skyrmions，它们已经在许多磁性材料中实现和研究。这种织构和准粒子巡回流动之间的动态耦合效应在磁学中非平衡现象和输运的广泛研究中引起了关注。金属和绝缘体中准粒子带的动量空间拓扑学重振了半导体、半金属、超导体和磁性绝缘体等材料科学的研究，着眼于不同拓扑相之间的不同形式的量子化响应和无缝传输。在这些发展的基础上，PI将沿着以下方向解决主要问题：利用基于空间离域拓扑不变量的守恒定律，通过有序和受阻的量子磁铁进行长距离传输；新出现的孤子流体和晶体的奇异流体动力学和弹性；以及发展一种电路理论形式，用于拓扑纠缠产生的可行的自旋和自旋热电子学方法。这项研究中探索的自旋电子结构和设备将提供超导量子电路的替代方案，作为一个多功能和可扩展的量子信息处理和计算平台。除了研究之外，PI还将继续参与加州大学洛杉矶分校加州纳米系统研究所赞助的一个成功的扩展项目，该项目为洛杉矶统一学区公立学校的高中生带来纳米科学和纳米技术实验，以及理论解释和演示。PI还将为加州大学洛杉矶分校的本科生研究体验项目开发一个以凝聚态理论为中心的组成部分，在该项目中，本科生与教师导师以及其他教授、研究人员和研究生一起进行暑期研究项目。

NONTECHNICAL SUMARYThis award supports theoretical research and education on developing a methodology for the description of spin transport in magnetic materials in analogy to hydrodynamics. Apart from carrying electric charge, electrons moving through materials carry with them a tiny magnetic moment called spin. Manipulation of those magnetic moments enables new kinds of electronic devices that utilize spin in addition to charge. There are circumstances under which the description of the transport of spins and of the magnetic arrangements (textures) that many spins collectively create can be achieved by analogy to the description of a fluid. The PI will develop a theoretical framework for describing how spin textures interact and flow through magnetic materials. The PI's research and collaboration with materials scientists and engineers at UCLA will help develop and support concepts for memory, logic, and communications devices that are based on materials that harness spin textures.In addition to research, the PI will continue and build upon his involvement with a successful outreach program run under the auspices of the UCLA California Nanosystems Institute, which brings nanoscience and nanotechnology experiments, along with theoretical explanations and presentations, to high-school students from public schools in the Los Angeles unified school district. The PI will also develop a condensed-matter-theory-centered component for UCLA's Research Experience for Undergraduates program, in which undergraduate students work with a faculty mentor, as well as other professors, researchers, and graduate students, on a summer research project.TECHNICAL SUMMARYThis award supports theoretical research and education towards developing the theory of real-space topological hydrodynamics in relation to fluctuations and flows of topological solitons in magnetic insulators. The interplay of heat flows and spin dynamics in magnetic systems shifted much of the interest in the field of spintronics onto collective forms of spin transport. Important examples are topological spin textures, such as chiral domain walls and skyrmions, which have been realized and studied in a number of magnetic materials. Dynamic coupling effects between such textures and itinerant flows of quasiparticles has garnered attention in broad studies of nonequilibrium phenomena and transport in magnetism. Momentum-space topology, for quasiparticle bands in metals and insulators, has revitalized materials science research in classes of semiconductors, semimetals, superconductors, as well as magnetic insulators, with an eye on unusual forms of quantized response and gapless transport at the boundaries between distinct topological phases.Drawing on these developments, the PI will address the main problems along the following directions: long-range transport through ordered and frustrated quantum magnets, utilizing conservation laws based on spatially-delocalized topological invariants; exotic hydrodynamics and elasticity of emergent solitonic fluids and crystals; and developing a circuit-theory formalism for topological entanglement production with feasible spintronic and spin-caloritronic means. Spintronic structures and devices explored in this research will offer an alternative to superconducting quantum circuits as a versatile and scalable platform for quantum information processing and computing.In addition to research, the PI will continue and build upon his involvement with a successful outreach program run under the auspices of the UCLA California Nanosystems Institute, which brings nanoscience and nanotechnology experiments, along with theoretical explanations and presentations, to high-school students from public schools in the Los Angeles unified school district. The PI will also develop a condensed-matter-theory-centered component for UCLA's Research Experience for Undergraduates program, in which undergraduate students work with a faculty mentor, as well as other professors, researchers, and graduate students, on a summer research project.