Frustration and Spin Fluctuations in Itinerant Magnets

流动磁铁中的挫败和旋转波动

• 批准号: 1903741
• 负责人: Emilia Morosan
• 金额: $ 48.39万
• 依托单位: William Marsh Rice University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-08-01 至 2024-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1903741&HistoricalAwards=false
• 关键词: Frustration; Spin; Fluctuations; Itinerant; Magnets

NON-TECHNICAL ABSTRACTThis project, supported by the Condensed Matter Physics program of the Division of the Materials Research, presents a systematic way to design and discover magnetic materials belonging to a rare class of compounds, those formed with non-magnetic constituents: itinerant magnets. Magnetic materials are ubiquitous in our modern world and they are at the heart of many technologies including memory storage, magnetic resonance imaging (MRIs) etc. While the applications of magnetic materials are clear, our fundamental understanding of their properties remains largely unknown, especially for those magnetic systems formed without known magnetic elements (like iron or rare earths). The understanding of the purely itinerant magnetism limit is inhibited by the scarcity of relevant compounds, which this project seeks to design and synthesize. An added novelty of this approach is the study of effects in itinerant magnets, related to the crystal structure. This proposal supports the training of undergraduate and graduate student researchers in the areas of crystal growth and materials characterization. The PI continues her ongoing outreach initiatives, which include open houses and science demonstrations at local public schools in addition to developing a new "science a la carte" program, aimed at complex science concepts accessible to young students.Technical abstract:This NSF proposal emphasizes experimental investigations of itinerant magnetic systems to explore the role of spin fluctuations and magnetic frustration in compounds without magnetic elements. New discoveries of two itinerant antiferromagnets, together with the only two known ferromagnets without magnetic elements, offer a platform for two main research thrusts: the study of correlations between the dimensionality and spin fluctuations of itinerant magnets, particularly in the quantum critical regime; the development of a new paradigm for frustration in itinerant magnetic systems. This project addresses issues currently at the forefront of condensed matter physics, such as quantum criticality and attendant non-Fermi liquid effects, and also frustration as a new dimension in a generalized phase diagram for quantum criticality. Our program aligns with the imperious societal need for design and discovery of new materials, while training the new generation of crystal growers. The PI continues her program providing hands-on science experience through the lab "open houses" for the public, training high school students and teachers through internships, and by implementing a "science a la carte" program for schools in the Houston area. This program provides science kits in line with the school science curriculum, together with demonstrations by the PI and her students, and handouts, aimed at fostering learning beyond the classroom.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

本项目由材料研究部凝聚态物理计划资助，提供了一种系统的方法来设计和发现属于一类稀有化合物的磁性材料，这些化合物是由非磁性成分形成的：巡回磁铁。磁性材料在我们的现代世界中无处不在，是包括记忆存储、磁共振成像等在内的许多技术的核心。虽然磁性材料的应用很清楚，但我们对其性质的基本了解在很大程度上仍不清楚，特别是对于那些没有已知磁性元素(如铁或稀土)形成的磁系统。由于缺乏相关化合物，人们对纯巡回磁性极限的理解受到阻碍，而本项目试图设计和合成相关化合物。这种方法的另一个新奇之处是研究与晶体结构有关的巡回磁铁中的效应。该提案支持在晶体生长和材料表征领域对本科生和研究生研究人员进行培训。PI继续她正在进行的推广活动，包括开放参观和在当地公立学校进行科学演示，此外还开发了一个新的“科学点菜”计划，旨在让年轻学生了解复杂的科学概念。技术摘要：这项NSF计划强调对巡回磁系统的实验研究，以探索自旋波动和磁挫折感在没有磁性元素的化合物中的作用。两个巡回反铁磁体的新发现，以及仅有的两个已知的没有磁性元素的铁磁体，为两个主要研究任务提供了平台：研究巡回磁体的维度和自旋涨落之间的关联，特别是在量子临界区域；发展巡回磁系统中受挫的新范式。这个项目解决了目前处于凝聚态物理前沿的问题，如量子临界性和伴随的非费米液体效应，以及作为量子临界性广义相图中新维度的挫折感。我们的计划符合社会对设计和发现新材料的迫切需求，同时也培养了新一代的晶体种植者。PI继续实施她的计划，通过实验室向公众提供实践科学体验，通过实习培训高中生和教师，并为休斯顿地区的学校实施“科学点菜”计划。该计划提供与学校科学课程一致的科学工具包，以及PI和她的学生的演示，以及旨在促进课外学习的讲义。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Symmetry-mode analysis for local structure investigations using pair distribution function data

使用对分布函数数据进行局部结构研究的对称模式分析

• DOI: 10.1107/s1600576723005794
• 发表时间: 2023
• 期刊: Journal of Applied Crystallography
• 影响因子: 6.1
• 作者: Hamilton, Parker K.;Moya, Jaime M.;Hallas, Alannah M.;Morosan, E.;Baral, Raju;Frandsen, Benjamin A.
• 通讯作者: Frandsen, Benjamin A.

Field-induced quantum critical point in the itinerant antiferromagnet Ti3Cu4

• DOI: 10.1038/s42005-022-00901-7
• 发表时间: 2020-10
• 期刊: Communications Physics
• 影响因子: 5.5
• 作者: J. M. Moya;A. Hallas;V. Loganathan;C. Huang;L. Kish;A. Aczel;J. Beare;Y. Cai;G. Luke;Franziska Weickert;A. Nevidomskyy;C. Malliakas;M. Kanatzidis;Shiming Lei;K. Bayliff;E. Morosan