CAREER: Skyrmion-Vortex Interactions in Ferromagnet-Superconductor Heterostructures

职业：铁磁体-超导异质结构中的斯格明子-涡旋相互作用

• 批准号: 2046925
• 负责人: Serena Eley
• 金额: $ 64.09万
• 依托单位: Colorado School of Mines
• 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: 2021-07-15 至 2023-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2046925&HistoricalAwards=false
• 关键词: CAREER; Skyrmion; Vortex; Interactions; Ferromagnet

Non-technical abstract:The field of spintronics is a rapidly advancing and disruptive research area, producing novel device schemes that are superior to conventional computing electronics. Conventional electronic elements use electron charge to store and transmit information. For example, the amount of charge accumulated on a capacitor may determine whether it contributes a “0” or a “1” binary digit. On the other hand, spintronic devices exploit another property of electrons, called spin (up, down, or canted), to encode information. These devices can in fact use spin currents to control logic operations faster and more energy efficiently than charge currents can accomplish in conventional semiconductor transistor-based logic. Spintronics devices typically consist of ferromagnets as the source of the spin current. Incorporating elements that are superconductors, which have no electrical resistance, can enhance the overall device performance and offer new functionalities, such as remarkably low-dissipation (energy loss) spin transport. Such ferromagnetic-superconductor structures are also constituents of schemes for topological quantum computing, an architecture that is predicted to be robust to environmental noise that plagues other quantum device platforms. This project investigates ferromagnetic-superconductor devices that could form building blocks of novel computing architectures by imaging nanoscale magnetic fields throughout the device and determining the effects of temperature and an applied current on the device operation. This effort also contributes to the development of a globally competitive quantum workforce in the U.S. by designing a novel lab course that teaches foundational skills for careers in quantum sensing and computing, and providing training in electronics to K-12 students at a local elementary school. Technical abstract:Ferromagnet-superconductor (FS) heterostructures are promising platforms for superconducting spintronics and topological quantum computing. In FS heterostructures, it is theoretically predicted that skyrmion-vortex pairs can form that are desirable for computing applications. The objective of this program is to design, fabricate, and study a system in which skyrmions and vortices co-exist and interact. Specifically, the research team studies proximity coupling in two different FS heterostructures: iron germanium telluride (FGT) - superconductor bilayers and arrays of FeGe islands under a superconducting layer. For both heterostructures, they employ magnetic force microscopy and electrical transport measurements to study the dynamics of magnetic textures that emerge in these devices under variable temperatures (down to 1.6 K) and magnetic fields (up to 12 T), determining the conditions under which skyrmions and vortices co-exist and bind. Proposed work includes studies of the effects of thermal energy and current-induced forces, and comparing the results to semiclassical theories describing skyrmion-vortex pair dynamics.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：自旋电子学领域是一个快速发展和颠覆性的研究领域，它产生了优于传统计算电子元件的新颖设备方案，它们使用电子电荷来存储和传输信息，例如累积的电荷量。另一方面，自旋电子器件利用电子的另一种特性，称为自旋（向上、向下或倾斜）来编码信息。事实上可以使用自旋电流来控制逻辑操作比传统的基于半导体晶体管的逻辑可以更快、更节能。自旋电子器件通常由铁磁体组成，作为自旋电流的源，其中包含没有电阻的超导体元件。 ，可以提高整体器件性能并提供新功能，例如异常低耗散（能量损失）的自旋输运，这种铁磁超导体结构也是拓扑量子方案的组成部分。该项目研究了铁磁超导体设备，该设备可以通过对整个设备中的纳米级磁场进行成像并确定温度的影响来构成新型计算架构的构建块。这项工作还通过设计一门新颖的实验室课程来教授量子传感和计算方面的职业技能，并为学生提供电子学培训，从而有助于在美国培养具有全球竞争力的量子劳动力。当地小学的 K-12 学生。技术摘要：铁磁体-超导体 (FS) 异质结构是超导自旋电子学和拓扑量子计算的有前途的平台，理论上预测可以形成理想的斯格明子-涡旋对。该项目的目标是设计、制造和研究斯格明子和涡旋共存并相互作用的系统，具体来说，研究团队研究两者的邻近耦合。不同的 FS 异质结构：碲化铁锗 (FGT) - 超导双层和超导层下的 FeGe 岛阵列 对于这两种异质结构，他们采用磁力显微镜和电输运测量来研究这些器件在可变条件下出现的磁性纹理的动力学。温度（低至 1.6 K）和磁场（高达 12 T），确定斯格明子和涡旋共存和结合的条件。拟议的工作包括研究热能和电流感应力的影响，并将结果与​​描述斯格明子-涡旋对动力学的半经典理论进行比较。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进行评估，被认为值得支持以及更广泛的影响审查标准。