CAREER: Synthetic design of structure-inspired magnetic topological materials

该奖项的全部或部分资金来自2021年美国救援计划法案（公法117-2.非技术保护大多数现代计算机和微电子技术都使用半导体硅，利用电子的电荷来存储，传输和处理信息。虽然硅在过去几十年中一直是技术进步的工具，但除了电荷之外，电子的固有自旋的使用为更薄，更快和更节能的设备带来了希望。然而，一个巨大的挑战在于设计和发现材料，使电荷和自旋之间的相互作用产生整体大于部分之和的性质。该项目的研究目标是设计，合成和研究材料，其中底层晶体结构在为电荷和自旋之间的耦合提供平台方面起着至关重要的作用，作为可能塑造未来技术的平台，例如基于自旋的电子学（自旋电子学）或量子计算。与研究工作相结合，该项目的教育目标是通过多种渠道为学生和更广泛的社区带来材料合成和表征：从代表性不足的群体中招募本科生和研究生;量子材料课程开发;以及为本科生和研究生组织材料合成和表征研讨会。该项目还希望通过GMU现有的K-12计划，如有抱负的科学家暑期实习计划和GMU STEM加速器计划，让高中生参与研究-他们通常看不到他们社区中的科学职业道路。发现和理解由于电子相关性和电子拓扑的组合效应而产生的涌现现象是当代凝聚态物理学的主要目标。本项目的研究目标是设计、发现和研究一个由材料的晶体结构介导的、在真实的或倒易空间中具有简并破缺统一原理的量子物质截面。具体而言，该项目侧重于：1）通过磁输运测量合成和研究特定类别的Kagome晶格磁体，其为在真实的和动量空间中产生的拓扑性质的相互作用提供独特的平台，以及2）合成和提供最近提出的共线反铁磁体的实验验证，由于晶体对称性，产生铁磁体中预期的性质，但没有净磁化并且不需要自旋-轨道耦合。因此，该项目旨在推进对电子拓扑结构和复杂磁性之间的相互作用以及简单磁性有序和晶体结构之间的相互作用的基本理解。它的最终目标是合成能够通过这些材料所包含的新兴现象来塑造未来技术和量子信息科学的材料。 这些性质适用于自旋电子学、无耗散电子学和量子计算。 与研究工作相结合，该项目的教育目标是通过多种渠道为学生和更广泛的社区带来材料合成和表征：从代表性不足的群体中招募本科生和研究生;量子材料课程开发;以及为本科生和研究生组织材料合成和表征研讨会。该项目还希望通过GMU现有的K-12项目，让高中生参与研究-他们通常看不到他们社区中的科学职业道路，如有抱负的科学家暑期实习计划和GMU STEM加速器计划。该奖项反映了NSF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。

This award is funded in whole or in part under the American Rescue Plan Act of 2021 (Public Law 117-2.NON-TECHNICAL DESCRIPTIONMost modern-day computers and microelectronics make use of the semiconductor silicon, which exploits the electron’s charge to store, transmit, and process information. Although silicon has been instrumental in technological advancements over the last several decades, use of the electron’s intrinsic spin, in addition to its charge, holds promise for thinner, faster and more energy efficient devices. A grand challenge, however, lies in the design and discovery of materials that allow the interplay between charge and spin to yield properties whose whole is greater than the sum of its parts. The research objective of this project is to design, synthesize and study materials where the underlying crystal structure plays crucial role in providing the platform for this coupling between charge and spin as a platform that can potentially shape future technologies, such as spin-based electronics (spintronics) or quantum computing. Integrated with the research efforts, the education goal of this project is to bring materials synthesis and characterization to students and the broader community in the greater DC-Maryland-Virginia (DMV) area through multiple channels: recruitment of both undergraduate and graduate students from underrepresented groups; curriculum development in quantum materials; and workshop organization on materials synthesis and characterization for undergraduate and graduate students. The project also aspires to engage high school students—who generally do not see science career paths represented in their communities—in research through existing K-12 programs at GMU, such as the Aspiring Scientists Summer Internship Program and the GMU STEM Accelerator Program. TECHNICAL DESCRIPTION Finding and understanding emergent phenomena arising due to the combined effect of electron correlations and electronic topology is a major goal of the contemporary condensed matter physics. The research goal of this project is to design, discover and investigate a cross-section of quantum matter with the unifying principle of degeneracy breaking in either the real or reciprocal space mediated by the crystal structure of the materials. Specifically, the project concentrates on: 1) synthesizing and studying by means of magnetotransport measurements a specific class of kagome lattice magnets that provide a unique platform for the interplay of topological properties arising both in the real and the momentum space, and 2) synthesizing and providing experimental validation of recently proposed collinear antiferromagnets which, by virtue of the crystalline symmetry, give rise to the properties expected in ferromagnets but without the net magnetization and without the requirement of spin-orbit coupling. As such, this project aims to advance the fundamental understanding of the interplay between electronic topology and complex magnetism, and the interplay between simple magnetic ordering and the crystal structure. Its ultimate goal is to synthesize materials that can shape future technology and quantum information science through the emergent phenomena these materials harbor. Such properties are applicable for spintronics, dissipationless electronics and quantum computing. Integrated with the research efforts, the education goal of this project is to bring materials synthesis and characterization to students and the broader community in the greater DC-Maryland-Virginia (DMV) area through multiple channels: recruitment of both undergraduate and graduate students from underrepresented groups; curriculum development in quantum materials; and workshop organization on materials synthesis and characterization for undergraduate and graduate students. The project also aspires to engage high school students—who generally do not see science career paths represented in their communities—in research through existing K-12 programs at GMU, such as the Aspiring Scientists Summer Internship Program and the GMU STEM Accelerator Program.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.