CAREER: Band-Topology of Multipolar Magnetic Excitations

职业：多极磁激励的能带拓扑

• 批准号: 2142554
• 负责人: Judit Romhanyi
• 金额: $ 68.79万
• 依托单位: University of California-Irvine
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-07-01 至 2027-06-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2142554&HistoricalAwards=false
• 关键词: CAREER; Band; Topology; Multipolar; Magnetic

This award is funded in part under the American Rescue Plan Act of 2021 (Public Law 117-2).NONTECHNICAL SUMMARYThis award supports theoretical research aimed at the discovery and understanding of exotic properties of magnetic quantum materials. Instead of examining the individual attributes of electrons, considering their collective behavior reveals many remarkable properties of matter, including the generation of magnetism. The interplay of the electrons' spin and orbital degrees of freedom can produce novel states that behave very differently from the original constituents and bear great relevance for technological applications. This project focuses on understanding the conditions for such emergent states of matter and aims to uncover new features that facilitate their experimental detection and control. Specifically, this research integrates theoretical tools rooted in the modern concepts of topology and symmetries to characterize novel magnetic states. Furthermore, it establishes a connection between the theoretical description and the materials' responses to different experimental probes. Considering real materials in collaboration with experimental groups is an integral part of the research design. The results of this study can open new routes to low-energy consuming reconfigurable devices that build on magnetism and optical control. This award also supports outreach efforts to decrease the STEM opportunity gap of students from underserved and marginalized communities. This will be addressed on multiple levels of education, from elementary to graduate school, aiming to spark interest in sciences, build scientist identity, reduce the preparation gap, and improve the retention of underrepresented minorities. In particular, the PI will initiate summer programs, a physics Bootcamp, and a biennial graduate summer school and join an existing outreach activity at her institution targeting middle school students to promote awareness of existing opportunities and to help them visualize a future in higher education.TECHNICAL SUMMARYThis award supports theoretical research aimed at the discovery and understanding of the exotic properties of quantum magnets. Magnetic materials endowed with a multi-component local Hilbert space have an extraordinary potential for realizing novel topological states. They admit unconventional multipole degrees of freedom, calling for a generalized approach to characterize their topology and experimental signatures. In particular, this research will explore how the enlarged local Hilbert spaces originating from the combination of spin, orbital, and lattice degrees of freedom can provide an internal structure to protect the nontrivial topologies. Furthermore, it will reveal how they can realize novel experimental probes for topological boundary modes based on the magneto-electric effect, surface-selective optical responses, and distinctive Hall signals. The results of this study will advance our understanding of the band-topology of multipole magnetic excitations and uncover unique experimental fingerprints for their detection and manipulation. Moreover, they will be directly relevant for a wide range of bosonic systems, including but not limited to photonic, acoustic, and mechanical lattices and artificial magnonic metamaterials.This award also supports outreach efforts to decrease the STEM opportunity gap of students from underserved and marginalized communities. This will be addressed on multiple levels of education, from elementary to graduate school, aiming to spark interest in sciences, build scientist identity, reduce the preparation gap, and improve the retention of underrepresented minorities. In particular, the PI will initiate summer programs, a physics Bootcamp, and a biennial graduate summer school and join an existing outreach activity at her institution targeting middle school students to promote awareness of existing opportunities and to help them visualize a future in higher education.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.

该奖项的部分资金来自2021年美国救援计划法案（公法117-2）。非技术性总结该奖项支持旨在发现和理解磁量子材料奇异特性的理论研究。考虑到电子的集体行为，而不是检查电子的个体属性，揭示了物质的许多显着属性，包括磁性的产生。电子的自旋和轨道自由度的相互作用可以产生新的状态，这些状态的行为与原始成分非常不同，并且与技术应用具有很大的相关性。该项目的重点是了解这种物质紧急状态的条件，并旨在发现有助于实验检测和控制的新特征。具体来说，这项研究整合了植根于拓扑和对称性的现代概念的理论工具，以表征新的磁状态。此外，它建立了理论描述和材料对不同实验探针的响应之间的联系。与实验组合作考虑真实的材料是研究设计的一个组成部分。这项研究的结果可以开辟新的路线，以低能耗的可重构设备，建立在磁性和光学控制。该奖项还支持外展工作，以减少来自服务不足和边缘化社区的学生的STEM机会差距。这将在从小学到研究生院的多个教育层次上解决，旨在激发对科学的兴趣，建立科学家身份，减少准备差距，并改善代表性不足的少数民族的保留。特别是，PI将启动暑期项目，物理训练营，两年一度的研究生暑期学校，并加入她所在机构针对中学生的现有外展活动，以提高对现有机会的认识，并帮助他们想象高等教育的未来。技术总结该奖项支持旨在发现和理解量子磁体奇异性质的理论研究。具有多分量局部希尔伯特空间的磁性材料具有实现新拓扑态的巨大潜力。他们承认非常规的多极自由度，要求一个广义的方法来描述他们的拓扑结构和实验签名。特别是，这项研究将探讨如何扩大局部希尔伯特空间起源于自旋，轨道和晶格自由度的组合可以提供一个内部结构，以保护非平凡的拓扑结构。此外，它将揭示他们如何能够实现新的实验探针的拓扑边界模式的基础上的磁电效应，表面选择性的光学响应，和独特的霍尔信号。这项研究的结果将推进我们的多极磁激励的带拓扑结构的理解，并发现其检测和操纵独特的实验指纹。此外，他们将直接与广泛的玻色子系统，包括但不限于光子，声学和机械晶格和人工magnonic metamaterials.This award also supports outreach efforts to reduce the STEM opportunity gap of students from underserved and marginalized communities.这将在从小学到研究生院的多个教育层次上解决，旨在激发对科学的兴趣，建立科学家身份，减少准备差距，并改善代表性不足的少数民族的保留。特别是，PI将启动暑期项目，一个物理训练营，和两年一度的研究生暑期学校，并参加她所在机构针对中学生的现有外展活动，以提高对现有机会的认识，并帮助他们设想高等教育的未来。该奖项反映了NSF的法定使命，并通过使用基金会的智力价值和更广泛的评估，被认为值得支持。影响审查标准。

项目成果

Where is the Quantum Spin Nematic?

量子自旋向列在哪里？

• DOI: 10.1103/physrevlett.130.116701
• 发表时间: 2023
• 期刊: Physical Review Letters
• 影响因子: 8.6
• 作者: Jiang, Shengtao;Romhányi, Judit;White, Steven R.;Zhitomirsky, M. E.;Chernyshev, A. L.
• 通讯作者: Chernyshev, A. L.