Quantum Phenomena in Solids

固体中的量子现象

• 批准号: 2116515
• 负责人: Leon Balents
• 金额: $ 40万
• 依托单位: University of California-Santa Barbara
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2116515&HistoricalAwards=false
• 关键词: Quantum; Phenomena; Solids

NONTECHNICAL SUMMARYThis award supports theoretical research on the quantum physics of electrons inside materials. Even a tiny amount of a solid contains an enormous number of electrons, which, when they coordinate their actions, can induce remarkable effects and useful material properties, such as magnetism, switching, and superconductivity. This project seeks to discover new examples of such effects and expand our understanding of existing ones. In particular, the research will study unusual magnets and conductors, make theoretical predictions for experiments to probe their novel quantum capabilities, and determine how to manipulate the electrons within these materials using electromagnetic fields. A core component of the study is to incorporate recently developed abstract theoretical ideas about ways in which electrons can cooperate quantum mechanically, known as entanglement and topological order, into practical proposals for experiments. The results of the research may be the basis of new technologies and quantum devices. All the research will be continuously compared with and referenced to real materials and experiments, with this feedback refining directions for theory to ensure maximum impacts in the laboratory.Training of undergraduate and graduate students and postdoctoral researchers is an integral component of this project. These junior scientists will learn forefront areas of condensed matter and quantum theory, as well as develop general scientific, communication, and computational proficiency, through mentorship and collaboration on the research. These skills prepare them to participate productively in the nation's quantum workforce.TECHNICAL SUMMARYThis award supports theoretical research on the quantum physics of quantum magnets and ordered topological metals, to discover the fundamental mechanisms in which electrons act together to produce new states of matter, and to predict what novel properties these states possess. The studies of quantum magnets will determine their dynamics in and out of equilibrium, providing experimentalists with clear signatures to seek in the laboratory, both for highly entangled (e.g. quantum spin liquid) states and for ordered ones. Furthermore, the research will design ways to control materials' properties in situ via oscillating fields. The projects on ordered topological metals address a different way to control materials' properties - their topology - through induced symmetry breaking order. The studies will determine how the topology of electronic states is modified by domains and topological defects of different types of order, such as magnetic domains and domain walls in topological magnets, and in turn, how this topology influences the properties and responses of those domains and defects. All the research will be continuously compared with and references to real materials and experiments, with such feedback refining directions for theory to ensure maximum impacts in the laboratory.Training of undergraduate and graduate students and postdoctoral researchers is an integral component of this project. These junior scientists will learn forefront areas of condensed matter and quantum theory, as well as develop general scientific, communication, and computational proficiency, through mentorship and collaboration on the research. These skills prepare them to participate productively in the nation's quantum workforce.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.

该奖项支持材料内部电子量子物理的理论研究。即使是极少量的固体也含有大量的电子，当它们相互协调作用时，可以产生显著的效应和有用的材料特性，如磁性、开关性和超导性。这个项目旨在发现这种影响的新例子，并扩大我们对现有影响的理解。特别是，该研究将研究不寻常的磁铁和导体，为实验做出理论预测，以探测它们的新量子能力，并确定如何使用电磁场操纵这些材料中的电子。这项研究的一个核心组成部分是将最近发展的关于电子量子力学合作方式的抽象理论思想，即纠缠和拓扑秩序，纳入实际的实验建议中。研究结果可能是新技术和量子器件的基础。所有的研究都将不断地与真实的材料和实验进行对比和参考，并通过这种反馈来完善理论方向，以确保在实验室中产生最大的影响。培养本科生、研究生和博士后研究人员是这个项目的一个组成部分。这些年轻的科学家将学习凝聚态物质和量子理论的前沿领域，并通过指导和合作在研究中发展一般的科学，交流和计算能力。这些技能使他们能够有效地参与到国家的量子劳动力中。该奖项支持量子磁体和有序拓扑金属的量子物理学理论研究，发现电子共同作用产生物质新状态的基本机制，并预测这些状态具有什么新特性。量子磁体的研究将决定它们在平衡状态下和平衡状态外的动力学，为实验家提供在实验室中寻找的清晰特征，无论是高度纠缠（例如量子自旋液体）状态还是有序状态。此外，该研究将设计通过振荡场来原位控制材料性能的方法。关于有序拓扑金属的项目解决了一种不同的方法来控制材料的性质-它们的拓扑-通过诱导对称破序。这些研究将确定不同类型顺序的畴和拓扑缺陷（如拓扑磁体中的磁畴和畴壁）如何改变电子态的拓扑结构，以及这种拓扑结构如何影响这些畴和缺陷的性质和响应。所有的研究都将不断地与真实的材料和实验进行对比和参考，这样的反馈完善理论方向，以确保在实验室中产生最大的影响。培养本科生、研究生和博士后研究人员是这个项目的一个组成部分。这些年轻的科学家将学习凝聚态物质和量子理论的前沿领域，并通过指导和合作在研究中发展一般的科学，交流和计算能力。这些技能使他们能够有效地参与到国家的量子劳动力中。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值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

Antichiral order and spin reorientation transitions of triangle-based antiferromagnets

• DOI: 10.1103/physrevb.106.l020403
• 发表时间: 2022-04
• 期刊: Physical Review B
• 影响因子: 3.7
• 作者: L. Balents

Free energy of twisting spins in Mn3Sn

• DOI: 10.1103/physrevb.106.l020402
• 发表时间: 2021-09
• 期刊: Physical Review B
• 影响因子: 3.7
• 作者: Xiaokang Li;Shan Jiang;Qi Meng;H. Zuo;Zengwei Zhu;L. Balents;Kamran Behnia

Rotation symmetry breaking in the normal state of a kagome superconductor KV3Sb5

• DOI: 10.1038/s41567-021-01479-7
• 发表时间: 2022-01-20
• 期刊: NATURE PHYSICS
• 影响因子: 19.6
• 作者: Li, Hong;Zhao, He;Zeljkovic, Ilija
• 通讯作者: Zeljkovic, Ilija

Twisted bilayer U(1) Dirac spin liquids

扭曲双层 U(1) 狄拉克自旋液体

• DOI: 10.1103/physrevb.106.144437
• 发表时间: 2022
• 期刊: Physical Review B
• 影响因子: 3.7
• 作者: Luo, Zhu-Xi;Seifert, Urban F.;Balents, Leon
• 通讯作者: Balents, Leon