Overseas Travel Grant: XMCD investigation of spin-orbit coupled heavy-metal/ferromagnet heterostructures at the Advanced Light Source, Berkeley

海外旅行资助：伯克利先进光源的自旋轨道耦合重金属/铁磁体异质结构的 XMCD 研究

• 批准号: EP/S021027/1
• 负责人: Niladri Banerjee
• 金额: $ 0.54万
• 依托单位: Loughborough University
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2018
• 资助国家: 英国
• 起止时间: 2018 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FS021027%2F1
• 关键词: Overseas; Travel; Grant; XMCD; investigation

This Overseas Travel Grant proposal seeks support from the EPSRC to cover the expenses related to travel and accommodation costs for the final phase of our beam time at the Advanced Light Source, Lawrence Berkeley National Laboratory to study the spin-orbit coupling in heavy-metal/ferromagnet multilayers. Spin-orbit coupling has recently been under intense focus in spintronics research, offering a revolutionary way to manipulate spins without ferromagnets which has driven classical spintronic devices. Spin-orbit coupling in heavy-metals in contact with ferromagnets has also been utilised to generate novel topological objects like magnetic skyrmions that offers the possibility of next-generation of ultra-dense data storage. Furthermore, recent work has shown a fundamental connection between spin-orbit coupling in heavy-metal/ferromagnet heterostructres and superconductivity that offers the possibility to develop a superconducting analogue of spin-orbit coupling-driven spintronics.Although the importance of spin-orbit coupled ferromagnets designed from these heterostructures is established, several materials-related questions remain. For example, the exact dependence of the strength of the spin-orbit coupling as a function of the nature of heavy-metal or ferromagnet remains poorly understood. A comprehensive study using different ferromagnets and heavy-metals will allow us to understand the microscopic origins of the spin-orbit coupling in these systems and ways to manipulate it. To investigate this, we have been awarded 24 shifts of X-ray Magnetic Circular Dichroism (XMCD) beamtime at the 6.3.1. beamline at the Advanced Light Source in Berkeley from 2017-2018. We have already attended 18 shifts and this proposal seeks funding to sponsor our last 6 shifts of beamtime (Proposal number ALS-09050, attached beamtime schedule letter). This beamline offers high accuracy XMCD measurements with a rapid magnetic field reversal minimising scan time. The highly-automated beamline also allows several samples to be measured in one loading making it ideal for our study involving a large number of samples.The results from this beamtime will allow us in future to quantitatively relate material parameters with the strength of spin-orbit coupling, thereby providing experimentalists a list to select materials from to specifically tailor the properties of these. Not only this will benefit the spintronics community, but will also allow us to consolidate our understanding of the newly discovered role of spin-orbit coupling in superconducting spintronics.

这项海外旅行补助金提案寻求EPSRC的支持，以支付与我们在劳伦斯伯克利国家实验室先进光源的最后阶段的光束时间相关的旅行和住宿费用，以研究重金属/铁磁多层膜中的自旋轨道耦合。自旋-轨道耦合是近年来自旋电子学研究的热点，它提供了一种革命性的方法来操纵自旋，而不需要铁磁体来驱动经典的自旋电子器件。与铁磁体接触的重金属中的自旋轨道耦合也被用来产生新的拓扑对象，如磁skyrmions，为下一代超密度数据存储提供了可能性。此外，最近的工作表明，在重金属/铁磁体异质结构中的自旋轨道耦合和超导性之间的基本联系，这提供了可能性，以开发一个超导模拟的自旋轨道耦合驱动的自旋电子学。虽然自旋轨道耦合铁磁体设计从这些异质结构的重要性是确定的，一些材料相关的问题仍然存在。例如，自旋-轨道耦合强度作为重金属或铁磁体性质的函数的确切依赖性仍然知之甚少。使用不同的铁磁体和重金属进行全面的研究将使我们能够理解这些系统中自旋轨道耦合的微观起源以及操纵它的方法。为了调查这一点，我们在6.3.1获得了24个X射线磁圆二色性（XMCD）束时间的偏移。2017年至2018年在伯克利的先进光源光束线。我们已经参加了18个班次，本提案寻求资助我们最后6个班次的射束时间（提案编号ALS-09050，随附射束时间安排函）。该光束线提供高精度XMCD测量，具有快速磁场反转，最大限度地减少扫描时间。高度自动化的光束线还允许在一次加载中测量多个样品，这使得它非常适合我们涉及大量样品的研究。该光束时间的结果将使我们能够在未来定量地将材料参数与自旋轨道耦合强度联系起来，从而为实验人员提供一个选择材料的列表，以专门定制这些材料的属性。这不仅将有利于自旋电子学社区，而且还将使我们能够巩固我们对超导自旋电子学中新发现的自旋轨道耦合作用的理解。