Collaborative Research: Ferrimagnetic Insulator Based Bilayers for Interface-Driven Topological Spin Textures

合作研究：基于亚铁磁绝缘体的双层界面驱动拓扑自旋纹理

• 批准号: 2225645
• 负责人: Xiaoqin Li
• 金额: $ 31.87万
• 依托单位: University of Texas at Austin
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-01 至 2025-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2225645&HistoricalAwards=false
• 关键词: Collaborative; Research; Ferrimagnetic; Insulator; Based

NON-TECHNICAL DESCRIPTIONData is everywhere. It is generated at an accelerating pace by the devices we carry with us, embedded electronics in our homes and cars, and increasingly powerful computers and servers. This requires an enormous amount of energy for data creation, storage, and transmission. Innovations in data storage and processing are needed, and conventional electronics based on semiconductors are not equal to the task. Spintronics combines electronics with spin, an intrinsic property of elementary particles. The goal of this project is to develop a new material platform for spintronics, allowing new types of devices for energy-efficient memory and computing. Investigators will focus on heterostructures consisting of ultrathin magnetic films with an adjacent metallic layer. Investigators will grow high-quality bilayer films, characterize interactions at the atomically sharp interfaces, and optimize their properties for use in applications. This fundamental research could lead to portable, nonvolatile memory devices that are smaller in size, higher in density, and more energy efficient than those currently available. Undergraduate and graduate students will be trained to work in the critical science and technology fields to support an innovation-driven economy. The PIs will jointly teach a course on spintronics as well as expand a course on “Being Human in Physics” to both of their institutions.TECHNICAL DESCRIPTIONMagnetic skyrmions are a promising candidate for future ultrahigh-density, high energy efficiency magnetic memory devices. They exhibit robust topological stability, have nanoscale sizes, and a low electrical current is required to write, erase, and transport them. In order for skyrmion-based next-generation magnetic memory technology to become a reality, the fundamental interactions at the interfaces of magnetic bilayers need to be thoroughly understood, including exchange coupling, Dzyaloshinskii-Moriya interaction, and magnetic anisotropy. These interactions need to be judiciously tuned to host nanometer-sized skyrmions at room temperature. To achieve this goal, the PIs pursue a collaborative research project on ultrathin magnetic garnet-based bilayers as energy-efficient spintronic materials. The team integrates epitaxial film growth with advanced spectroscopy methods and aims to achieve the following goals: (i) establishing the structure-property correlation via a rapid feedback loop of growth and spectroscopy characterization; (ii) optimizing bilayers for skyrmions with desirable characteristics and chiral domain wall motions with record-breaking velocity; and (iii) exploring a new class of bilayers consisting of an epitaxial ferrimagnetic insulator film and a van der Waals overlayer.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.

非技术性描述无处不在。它是由我们随身携带的设备、家庭和汽车中的嵌入式电子产品以及日益强大的计算机和服务器加速产生的。这需要大量的能量来创建、存储和传输数据。需要在数据存储和处理方面进行创新，而基于半导体的传统电子产品无法胜任这项任务。自旋电子学将电子学和自旋结合在一起，自旋是基本粒子的一种固有属性。该项目的目标是开发一种新的自旋电子学材料平台，使新型设备能够用于节能存储和计算。研究人员将把重点放在由超薄磁性薄膜和相邻金属层组成的异质结构上。研究人员将生长高质量的双层薄膜，表征原子锐化界面上的相互作用，并优化其性能以用于应用。这项基础研究可能导致便携式、非易失性存储设备比目前可用的设备更小、更高密度和更节能。培养本科生和研究生到关键科技领域工作，支撑创新驱动经济。PIS将联合教授一门关于自旋电子学的课程，并将一门关于在物理上成为人类的课程扩展到他们的两个机构。技术描述磁性天子体是未来超高密度、高能效磁存储设备的一个有前途的候选者。它们表现出强大的拓扑稳定性，具有纳米级大小，需要低电流来写入、擦除和传输它们。为了使基于Skyrmion的下一代磁记忆技术成为现实，需要彻底了解磁性双层界面上的基本相互作用，包括交换耦合、Dzyaloshinskii-Moriya相互作用和磁各向异性。这些相互作用需要进行明智的调整，以在室温下容纳纳米大小的天空微子。为了实现这一目标，PIS开展了一项合作研究项目，将基于超薄磁性石榴石的双层薄膜作为高能效的自旋电子材料。该团队将外延薄膜生长与先进的光谱方法相结合，旨在实现以下目标：(I)通过生长和光谱表征的快速反馈循环建立结构与性质的相关性；(Ii)针对具有理想特性的Skyrmions和创纪录的手性磁区壁运动优化双层膜；以及(Iii)探索由外延铁磁绝缘膜和van der Waals覆盖层组成的新型双层膜。