Atomic magnetism of skyrmion lattices: Probing Dzyaloshinskii-Moriya interactions using advanced low temperature conversion electron Mössbauer spectroscopy

我的研究计划集中在研究纳米级磁性的机制，特别是在界面上。特别令人感兴趣的是了解被称为Skyrmions的磁性结构的纳米级漩涡的稳定性。Skyrmions的行为就像粒子，可以移动、创造和湮灭。它们将使自旋电子学发生革命性的变化，因为它们可以执行算术逻辑，并在室温下使用电流提供超低能量信息存储和射频技术。创造和控制Skyrmions需要知道如何操纵界面上相邻原子的自旋轨道耦合(SOC)磁性。光谱学是一种用于量化SOC的自然工具，穆斯堡尔光谱学非常适合于探测SOC和界面磁性。Skyrmions的手性决定了大部分性质，手性相互作用由Dzyaloshinskii-Moriya相互作用(DMI)稳定。在20世纪60年代和70年代，穆斯堡尔光谱学是量化块状化合物中DMI的关键，并确定了DMI驱动的磁性的基本物理，这些磁性现在用于天空微子薄膜。有了拟议的设备以及我在光谱学和新探测器物理方面的专业知识，我打算开辟一条了解Skyrmions界面物理的新途径。*这项设备提案是关于具有5至300K(-270至25摄氏度)温度能力的穆斯堡尔制冷系统。它将为天空离子(和其他)薄膜上的新型转换电子穆斯堡尔谱实验提供一个无振动和温度控制的环境。将这项技术更新到薄膜上的挑战是巨大的，但我的团队处于成功的最佳位置。使用建议设备的实验将提供关键信息，并补充我的团队使用的其他技术，例如也探测SOC磁性的x射线同步加速器光谱仪。总体而言，我的HQP发现的新见解肯定会显著增强对SOC的理解，并从SOC效应、各向异性和DMI识别界面上的过程物理。这一新知识将远远超越天空微电子薄膜，应用于当前和未来信息存储(例如，介质和传感)下的界面上的磁性。希捷科技研发部门与行业合作者的知识转化将融入新技术。光谱学是我研究和HQP培训的核心，所需的设备将促进这两方面的发展。我们用这台设备所做的研究将让我的HQP学习尖端仪器的设计和建造(包括可转移到先进制造的新的3D打印和设计技能)、真空系统、低温、探测器、快速电子学和计算机数据采集。我的HQP通过这种设备学到的技能将在他们以后的研究和技术行业的职业生涯中发挥特别大的作用。

My research program is focused on the study of the mechanisms responsible for nanoscale magnetism, especially at interfaces. Of special interest is understanding the stabilization of the nanosized swirls of magnetic texture called skyrmions. Skyrmions behave as particles and can be moved, created and annihilated. They will revolutionize spintronics as they can be made to perform arithmetic logic, and offer ultra low energy information storage and radio frequency technologies at room temperature using electrical currents. Creating and controlling skyrmions requires knowing how to manipulate the spin-orbit coupling (SOC) magnetism of neighbouring atoms at interfaces. Spectroscopy is a natural tool to use to quantify SOC, and Mössbauer spectroscopy is ideally suited to probe the SOC and interfacial magnetism. The chirality of skyrmions determines most properties, and the chiral interactions are stabilized by the Dzyaloshinskii-Moriya interaction (DMI). In the 1960s and 70s, Mössbauer spectroscopy was key to quantifying DMI in bulk compounds, and identifying the underlying physics of DMI-driven magnetism that are now used in skyrmionic thin films. With the proposed equipment and my expertise in spectroscopy and new detector physics, I intend to open up a new avenue towards understanding the interface physics of skyrmions.******This equipment proposal is for a Mössbauer refrigeration system with 5 to 300 K (-270 to 25C) temperature capability. It will provide a vibration-free and temperature controlled environment for novel conversion electron Mössbauer spectroscopy experiments on skymionic (and other) thin films. The challenges of updating this technique to thin films are significant, but my group is optimally positioned to succeed. The experiments using the proposed equipment will provide key information and complement the other techniques my group uses, such as x-ray synchrotron spectroscopies that also probe SOC magnetism. Overall, the new insights my HQP discover are sure to enhance significantly the understanding of SOC, and the identification of the physics of processes at interfaces from SOC effects, anisotropy, and DMI. This new knowledge will apply well beyond skyrmionic films to the magnetism at interfaces that underlie current and future information storage (e.g. media and sensing). Knowledge translation with industrial collaborators at Seagate Technology R&D will feed into new technologies. Spectroscopy is central to my research and HQP training, and the requested equipment will advance both. The research we do with this equipment will have my HQP learn cutting-edge instrument design and construction (including new 3D printing and design skills that are transferable to advanced manufacturing), vacuum systems, cryogenics, detectors, fast electronics and computer data acquisition. The skills my HQP learn with this equipment will serve them exceptionally well later in their careers in research- and technology-based industries.