Probing novel phases of matter in van der Waals magnet Fe5-xGeTe2

探测范德华磁铁 Fe5-xGeTe2 中物质的新相

• 批准号: 2129879
• 负责人: Wencan Jin
• 金额: $ 52.32万
• 依托单位: Auburn University
• 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: 2021-08-15 至 2024-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2129879&HistoricalAwards=false
• 关键词: Probing; novel; phases; matter; van

Nontechnical abstractVan der Waals materials have atomically thin layers that are vertically stacked and have weak interlayer bonds. Graphite is one example. They can be fabricated into two-dimensional forms, which are of tremendous interest for the next generation nanometer-scale electronics. Recently, intrinsic magnetic order was demonstrated in two-dimensional van der Waals materials opening up new opportunities in data storage and information processing. Van der Waals magnetic materials are also of interest in fundamental condensed matter physics, because they possess appreciable interactions between the crystal structure, electronic states, and magnetic order that could lead to novel phases of matter with unique properties. This project will establish the relationships between the structural, electronic, and magnetic properties of a new van der Waals magnetic material with a high magnetic transition temperature and complex magnetic order. Understanding these properties will help in the design of high-efficiency electronic devices. The research goals are accomplished through comprehensive investigations combining multiple state-of-the-art experimental techniques. The research activities involve collaboration with scientists from different disciplines, which provides extensive training for graduate and undergraduate students at Auburn University. The experiments to be carried out at the national laboratories will promote the students’ professional development. The principal investigators will integrate the research topics into two existing courses and will continue to participate in the K-12 education under established local outreach programs. Technical abstractRecently, Fe5–xGeTe2 emerges as a new member in van der Waals magnetic materials with high Curie temperature and good stability in ambient conditions. Remarkably, in this compound, the complex atomic structure, together with the distinct electronic states and spin moments on the nonequivalent Fe sites can strongly impact the magnetic order. In this project, the interplay between the crystal structure, electronic states, and magnetic order will be investigated, to develop an in-depth understanding of the novel phases of matter in Fe5–xGeTe2. Specifically, this project consists of three intercrossing objectives: 1) elucidate the connection between crystal structure and magnetism; 2) reveal the interplay of electronic states and magnetic order; and 3) realize electric control of magnetization in Fe5–xGeTe2-based van der Waals heterostructures. The research team employs a unique toolset combining nonlinear optics, synchrotron-based photoemission spectroscopy/microscopy, and electro- and magnetic-transport techniques to identify the properties of this compound. Our findings will lead to the fundamental understanding of the interactions between lattice, charge, orbital, and spin degrees of freedom in two-dimensional quantum materials and open up new avenues in designing spintronic devices. This grant promotes the interdisciplinary research effort at Auburn University and the long-term collaboration between Auburn University and national laboratories.This project is jointly funded by the Electronic and Photonic Materials program in the Division of Materials Research and the Established Program to Stimulate Competitive Research (EPSCoR).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.

非技术抽象的der waals材料具有垂直堆叠且层间键较弱的原子薄层。石墨是一个例子。它们可以被制造成二维形式，对于下一代纳米尺度电子设备而言，它们引起了极大的兴趣。最近，在二维范德华（Van der Waals）材料中证明了固有的磁顺序，从而为数据存储和信息处理开辟了新的机会。范德华的磁性材料也对基本冷凝物理物理学也很感兴趣，因为它们在晶体结构，电子状态和磁性方面具有可观的相互作用，这些相互作用可能导致具有独特特性的物质的新阶段。该项目将建立具有高磁性过渡温度和复杂磁性的新范德华磁性材料的结构，电子和磁性性能之间的关系。了解这些特性将有助于设计高效电子设备。研究目标是通过结合多种最先进的实验技术的全面研究来实现的。研究活动涉及与来自不同学科的科学家的合作，这些科学家为奥本大学的研究生和本科生提供了广泛的培训。在国家实验室进行的实验将促进学生的专业发展。首席调查人员将将研究主题纳入两个现有课程，并将继续根据既定的当地外展计划参加K-12教育。技术突出地，Fe5 – Xgete2在范德华的磁性材料中成为新成员，其温度较高，在环境条件下稳定良好。值得注意的是，在这种化合物中，复杂的原子结构以及不同的电子状态以及在非效率位点上的旋转力矩可以强烈影响磁序。在这个项目中，将研究晶体结构，电子状态和磁性秩序之间的相互作用，以深入了解Fe5-Xgete2中物质的新阶段。具体而言，该项目由三个间断目标组成：1）阐明晶体结构和磁性之间的联系； 2）揭示电子状态和磁性的相互作用； 3）实现基于Fe5 – Xgete2的范德华异质结构中磁化的电力控制。研究团队采用了独特的工具集，结合了非线性光学元件，基于同步加速器的光发射光谱/显微镜以及电磁转运技术来识别该化合物的性质。我们的发现将导致对二维量子材料中晶格，电荷，轨道和自旋自由度之间相互作用之间的相互作用的基本理解，并在设计自旋设备时开辟了新的途径。该赠款促进了奥本大学的跨学科研究工作，以及奥本大学和国家实验室之间的长期合作。该项目由材料研究部的电子和光子材料计划共同资助，材料研究部和既定计划刺激竞争性研究（EPSCOR）的既定计划（EPSCOR）。这一奖项反映了NSF的法定任务和范围的范围。

项目成果

Magnetism and spin dynamics in room-temperature van der Waals magnet Fe5GeTe2

• DOI: 10.1088/2053-1583/ac2028
• 发表时间: 2021-10-01
• 期刊: 2D MATERIALS
• 影响因子: 5.5
• 作者: Alahmed, Laith;Nepal, Bhuwan;Li, Peng
• 通讯作者: Li, Peng

Effects of Temperature and Structural Geometries on a Skyrmion Logic Gate

• DOI: 10.1109/ted.2021.3130217
• 发表时间: 2022-04
• 期刊: IEEE Transactions on Electron Devices
• 影响因子: 3.1
• 作者: Chunli Tang;Laith Alahmed;Jihao Xu;Maokang Shen;Nicholas Alex Jones;Mehdi Sadi;Ujjwal Guin;W. Zhao;Peng Li

Sky-TCAM: Low-Power Skyrmion-Based Ternary Content Addressable Memory

• DOI: 10.1109/ted.2023.3274506
• 发表时间: 2023-07
• 期刊: IEEE Transactions on Electron Devices
• 影响因子: 3.1
• 作者: Ruifu Zhang;Student Member Ieee Chunli Tang;Xiaozhen Sun Mengyuan;Member Ieee Peng Li;Xiaomin Cheng;Fellow Ieee Sharon Hu;Wencan Jin;Mengyuan Li

Engineering metal oxidation using epitaxial strain

• DOI: 10.1038/s41565-023-01397-0
• 发表时间: 2023-05-22
• 期刊: NATURE NANOTECHNOLOGY
• 影响因子: 38.3
• 作者: Nair, Sreejith;Yang, Zhifei;Jalan, Bharat
• 通讯作者: Jalan, Bharat