Frustrated Quantum Magnetism in Insulators and Metals

绝缘体和金属中受挫的量子磁性

• 批准号: 0308945
• 负责人: Patrick Lee
• 金额: $ 24万
• 依托单位: Massachusetts Institute of Technology
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-09-01 至 2006-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0308945&HistoricalAwards=false
• 关键词: Frustrated; Quantum; Magnetism; Insulators; Metals

This award supports theoretical research and education on the quantum theory of localized magnetic moments in diverse electronic environments in solids. Specific areas of research include the physics of geometric frustration of quantum magnetism in insulating materials and the interplay between possibly frustrated inter-moment exchange and coupling between local moments and conduction electrons in metallic materials. Emphasis will be on understanding low temperature phenomena where quantum mechanical effects dominate. The PI aims to clarify the nature of the ground states and low energy excitations suggested by experiments or numerical calculations on several low-dimensional insulating frustrated quantum magnets. Field theoretical methods will be developed with an aim to obtaining physical insight. The PI will explore whether frustrated quantum magnets display excitations with fractional quantum numbers. The PI seeks to bridge the gap between theory and experiments in this active area of condensed matter physics. The PI will also study Kondo lattice models for metallic systems with localized magnetic moments, for example LiVO. Various phenomena discovered in these systems originate in the competition between possibly frustrated magnetic exchange between the local moments and the interaction between the local moments and the conduction electrons.This award also supports education at the graduate level in advanced theoretical condensed matter physics. The PI plans to involve undergraduate students in the research. %%%This award supports fundamental theoretical condensed matter physics research on phenomena that arise from geometrical frustration of quantum magnetic materials and the interaction between magnetic moments localized on particular atomic sites with itinerant conduction electrons. Geometrical frustration occurs when the interactions between magnetic moments cannot be simply satisfied because of the geometrical arrangement of the moments on the crystal lattice. This is fundamental research in an active and challenging area that involves strongly correlated electron materials including heavy fermion materials and quantum magnets like Cs2CuCl4. Research in this area has revealed subtle and beautiful phenomena in condensed matter physics and provides the intellectual foundation for future materials and device technologies. This award also supports education at the graduate level in advanced theoretical condensed matter physics. The PI plans to involve undergraduate students in the research. ***

该奖项支持在固体中不同电子环境中局部磁矩的量子理论的理论研究和教育。具体的研究领域包括绝缘材料中量子磁性的几何挫折物理学，以及可能受挫折的矩间交换和局部矩与金属材料中传导电子之间的耦合之间的相互作用。重点将放在理解量子力学效应占主导地位的低温现象。PI的目的是澄清的基态和低能量激发的实验或数值计算几个低维绝缘受抑量子磁体的建议的性质。场理论方法将被开发，目的是获得物理洞察力。PI将探索受挫折的量子磁体是否显示分数量子数的激发。PI旨在弥合凝聚态物理学这一活跃领域的理论与实验之间的差距。PI还将研究具有局部磁矩的金属系统的近藤晶格模型，例如LiVO。在这些系统中发现的各种现象起源于局部磁矩之间可能受抑的磁交换与局部磁矩与传导电子之间的相互作用之间的竞争。该奖项还支持高级理论凝聚态物理学的研究生教育。PI计划让本科生参与研究。该奖项支持基础理论凝聚态物理学的研究，这些研究涉及量子磁性材料的几何挫折以及特定原子位置上的磁矩与巡回传导电子之间的相互作用。当磁矩之间的相互作用由于磁矩在晶格上的几何排列而不能简单地得到满足时，就会发生几何阻挫。这是一个活跃和具有挑战性的领域的基础研究，涉及强相关电子材料，包括重费米子材料和量子磁体，如Cs2CuCl 4。这一领域的研究揭示了凝聚态物理中微妙而美丽的现象，并为未来的材料和器件技术提供了知识基础。该奖项还支持高等理论凝聚态物理学的研究生教育。PI计划让本科生参与研究。***