CAREER: Emergent Phases of Correlated Electrons in Materials with Spin-Orbit Coupling and Magnetic Frustration

职业：具有自旋轨道耦合和磁挫败的材料中相关电子的涌现相

• 批准号: 1511768
• 负责人: Natalia Perkins
• 金额: $ 40.05万
• 依托单位: University of Minnesota-Twin Cities
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-09-01 至 2019-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1511768&HistoricalAwards=false
• 关键词: CAREER; Emergent; Phases; Correlated; Electrons

TECHNICAL SUMMARYThis award supports theoretical on novel quantum phases that arise from the collective behavior of correlated electrons in the presence of strong spin-orbit coupling and frustration. The main focus is on 5d transition metal oxides, such as iridates and osmates, in which spin-orbit-coupling is comparable to, or larger than Coulomb energy. Specific 5d transition metal oxide systems have recently attracted a lot of theoretical and experimental attention because of unusual hierarchy of interactions, extended nature of 5d-orbitals, and high sensitivity to crystal fields. Because of these properties 5d systems are candidate materials for the realization of various emergent quantum phases, such as spin liquids, topological insulators, Weyl semimetals, and novel magnetically ordered Mott insulators.The PI aims to develop and analyze effective spin-orbital models which describe the low-energy physics of correlated systems in the presence of strong spin-obit coupling. The PI plans to study the ground state phase diagrams of these models and identify the nature of possible quantum states and phase transitions with an emphasis on studying finite temperature properties of these models, as the presence of anisotropic interactions in these models significantly affects the nature of finite temperature phase transitions. The PI will also study the effects of doping, as this can give rise to high-temperature superconductivity in these systems.Another thrust of the research is devoted to the analysis of elementary excitations in systems with strong spin-orbit-coupling. The PI plans to use a new computational framework to study quasiparticles in the magnetically ordered ground state in materials with strong spin-orbit-coupling, which she has recently developed. The method is quite useful for interpreting data obtained by the resonant inelastic x-ray scattering, which currently is the most effective tool to study the dispersion of elementary magnetic excitations across the whole Brillouin zone. The PI will also apply the method to analyze the effects of strong spin-orbit-coupling in Raman scattering from iridates and osmates. The PI?s ultimate goal is to provide a better understanding and description of existing experimental data and to generate verifiable predictions for future experiments.This project will be carried out in collaboration with collaborators from Europe and Japan. The collaboration brings an international dimension to the education of graduate students involved in the project. The PI plans to develop an advanced course in strongly correlated phenomena in complex materials and systems with special emphasis on new trends in magnetism and transport phenomena. In collaboration with other local faculty, the PI will create a Wisconsin Winter School on Modern Condensed Matter and Quantum Information and will organize short-term courses of condensed matter physics. This Winter School will introduce young researchers to various specific problems in the field and will also improve collaboration between faculty, students, and postdocs from different campuses of the University of Wisconsin System. The PI will also deliver a series of annual lectures for High School students and Physics lectures and seminars in support of the physics department outreach activity. The lectures will include the topics of quantum mechanics, computer science, and the future of material science.NONTECHNICAL SUMMARY This award supports theoretical and computational research and educational activities aimed at advancing our understanding of materials, in which the electron spin, an intrinsic quantum mechanical property of electrons, and the motion of the electron in a material strongly interact with each other, known as the spin-orbit interaction. The relevant materials are oxides that include transition metals, specifically iridium and osmium, in which the way the atoms are organized in space leads to a spin or spatial distribution of electrons which can occur in many nearly equivalent and hence, competing ways. The PI will focus on the case where the spin-orbit interaction dominates the familiar Coulomb interaction between electrons that arises from the electron charge. Achieving a theoretical understanding of the resulting properties of these materials in which the interactions among electrons lead to strong correlations in their motions is challenging. Interest in these systems stems in part from the richness of their novel properties: the unexpected variety of ways the electrons organize themselves, which leads, for example, to various forms of magnetism, the transformations among these states, and new phenomena that can arise in these iridium and osmium bearing materials. The PI will use theoretical and computational methods to investigate the physical properties of these transition metal oxides, predict new effects in these materials, and contribute to understanding the intriguing results of experiments. This project will be carried out in collaboration with collaborators from Europe and Japan. The collaboration brings an international dimension to the education of graduate students involved in the project. The PI plans to develop an advanced course in strongly correlated phenomena in complex materials and systems with special emphasis on new trends in magnetism and transport phenomena. In collaboration with other local faculty, the PI will create a Wisconsin Winter School on Modern Condensed Matter and Quantum Information and will organize short-term courses of condensed matter physics. This Winter School will introduce young researchers to various specific problems in the field and will also improve collaboration between faculty, students, and postdocs from different campuses of the University of Wisconsin System. The PI will also deliver a series of annual lectures for High School students and Physics lectures and seminars in support of the physics department outreach activity. The lectures will include the topics of quantum mechanics, computer science, and the future of material science.

技术摘要这一奖项支持理论上的新型量子阶段，这些量子阶段是由相关电子在存在强旋转轨道耦合和挫败感的情况下产生的。主要的重点是5D过渡金属氧化物，例如虹膜和渗透压，其中自旋 - 轨道偶联与库仑能相当或大。由于相互作用的异常层次，5D轨道的扩展性质以及对晶体场的高灵敏度，特定的5D过渡金属氧化物系统最近引起了许多理论和实验性关注。由于这些特性，5D系统是实现各种新兴量子相的候选材料，例如自旋液体，拓扑绝缘子，Weyl半学和新颖的磁性莫特绝缘子。 PI计划研究这些模型的基态相图，并确定可能的量子状态和相变的性质，重点是研究这些模型的有限温度性能，因为这些模型中各向异性相互作用的存在显着影响有限温度相变的性质。 PI还将研究掺杂的效果，因为这可能会引起这些系统中的高温超导性。研究的另一个推力是分析具有强旋转型偶联的系统的基本激发。 PI计划使用新的计算框架在具有强旋轨偶联的材料中以磁性有序的基态研究准颗粒，她最近开发了。该方法对于解释通过谐振非弹性X射线散射获得的数据非常有用，该数据目前是研究整个Brillouin区域基本磁激励分散的最有效工具。 PI还将采用该方法来分析来自虹膜和渗透液的拉曼散射中强旋转轨道偶联的影响。 PI的最终目标是提供对现有实验数据的更好理解和描述，并为将来的实验产生可验证的预测。该项目将与欧洲和日本的合作者合作进行。该合作为参与该项目的研究生的教育带来了国际维度。 PI计划在复杂材料和系统中开发高级课程，并特别强调磁性和运输现象的新趋势。 与其他当地教师合作，PI将建立一所威斯康星州冬季学校，讲述现代凝聚的物质和量子信息，并将组织凝结物理学的短期课程。这位冬季学校将向年轻的研究人员介绍该领域的各种特定问题，还将改善威斯康星大学系统不同校园的教职员工，学生和博士后之间的合作。 PI还将为高中生和物理讲座和研讨会提供一系列年度演讲，以支持物理部门外展活动。讲座将包括量子力学，计算机科学和材料科学的未来的主题。本科摘要该奖项支持理论和计算研究和教育活动，旨在促进我们对材料的理解，在该材料中，电子旋转，一种固有的量子力学特性，电子的电子特性，以及材料在材料中与对方相互作用的材料中的电子中的动作，与对方相互作用，与对方相互作用。相关的材料是包括过渡金属，特别是虹膜和osmium的氧化物，其中原子在太空中组织的方式导致电子的自旋或空间分布，这些分布可能以几乎等效的方式发生，因此可以竞争。 PI将重点放在自旋轨道相互作用主导熟悉的电子之间熟悉的库仑相互作用的情况下。 对这些材料的产生特性进行理论理解，在这些材料中，电子之间的相互作用导致其运动的强烈相关性是具有挑战性的。对这些系统的兴趣部分源于它们的新颖性能的丰富性：电子自身组织自己的意外种类，例如，这些方式引起了各种形式的磁性，这些状态之间的转换以及在这些虹膜和oSmium轴承材料中可能出现的新现象。 PI将使用理论和计算方法研究这些过渡金属氧化物的物理特性，预测这些材料的新作用，并有助于理解实验的有趣结果。该项目将与欧洲和日本的合作者合作进行。该合作为参与该项目的研究生的教育带来了国际维度。 PI计划在复杂材料和系统中开发高级课程，并特别强调磁性和运输现象的新趋势。 与其他当地教师合作，PI将建立一所威斯康星州冬季学校，讲述现代凝聚的物质和量子信息，并将组织凝结物理学的短期课程。这位冬季学校将向年轻的研究人员介绍该领域的各种特定问题，还将改善威斯康星大学系统不同校园的教职员工，学生和博士后之间的合作。 PI还将为高中生和物理讲座和研讨会提供一系列年度演讲，以支持物理部门外展活动。讲座将包括量子力学，计算机科学和材料科学的未来的主题。