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.

非技术摘要范德华材料具有垂直堆叠的原子薄层，并且具有弱的层间键合，它们可以被制造成二维形式，这对下一代纳米级电子学非常感兴趣。二维范德华材料中证明了固有磁序，为数据存储和信息处理开辟了新的机遇。范德华磁性材料也引起了基础凝聚态物理学的兴趣，因为它们具有。晶体结构、电子态和磁序之间的明显相互作用可能会产生具有独特性质的新物质相。该项目将建立一种新型范德华磁性材料的结构、电子和磁性之间的关系。高磁转变温度和复杂的磁序将有助于高效电子器件的设计，研究目标是通过结合多种最先进的实验技术来实现的。来自不同学科的科学家，为他们提供了广泛的培训奥本大学研究生和本科生将在国家实验室进行的实验将促进学生的综合专业发展，主要研究人员将把研究课题纳入现有的两门课程中，并将继续参与K-12教育。技术摘要最近，Fe5-xGeTe2 成为范德华磁性材料的新成员，具有高居里温度和在环境条件下良好的稳定性，值得注意的是，在这种化合物中，具有复杂的原子结构以及独特的电子。非等价 Fe 位点上的态和自旋矩可以强烈影响磁序。在该项目中，将研究晶体结构、电子态和磁序之间的相互作用，以深入了解物质的新相。具体而言，该项目包括三个交叉目标：1）阐明晶体结构与磁性之间的联系；2）揭示电子态和磁序的相互作用；3）实现磁化的电控制。基于 Fe5-xGeTe2 的范德华异质结构，研究小组采用了独特的工具集，结合了非线性光学、基于同步加速器的光电子能谱/显微镜以及电和磁传输技术来识别这种化合物的特性。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的基本理解，并为设计自旋电子器件开辟了新途径。促进奥本大学的跨学科研究工作以及奥本大学与国家实验室之间的长期合作。该项目由材料研究部电子和光子材料项目和刺激竞争性研究既定项目（EPSCoR）共同资助该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

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

室温范德华磁体 Fe5GeTe2 中的磁性和自旋动力学

• DOI: 10.1088/2053-1583/ac2028
• 发表时间: 2021-03-24
• 期刊: 2D Materials
• 影响因子: 5.5
• 作者: Laith Alahmed;Bhuwan Nepal;Juan Macy;Wenkai Zheng;Brian Casas;A. Sapkota;N. Jones;A. Mazza
• 通讯作者: A. Mazza

Engineering metal oxidation using epitaxial strain

利用外延应变进行工程金属氧化

• 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: Sreejith Nair;Z. Yang;Dooyong Lee;Silu Guo;J. Sadowski;S. Johnson;Abdul Saboor;Yan Li;Hua Zhou;R. Comes;Wencan Jin;K. Mkhoyan;A. Janotti;B. Jalan
• 通讯作者: B. Jalan

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

Sky-TCAM：基于斯格明子的低功耗三元内容可寻址存储器

• DOI: 10.1109/ted.2023.3274506
• 发表时间: 2023-07-01
• 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
• 通讯作者: Mengyuan Li

Effects of Temperature and Structural Geometries on a Skyrmion Logic Gate

温度和结构几何形状对斯格明子逻辑门的影响

• DOI: 10.1109/ted.2021.3130217
• 发表时间: 2022-04-01
• 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
• 通讯作者: Peng Li