Materials World Network: Scanned Probe Studies of FMR Driven Spin Injection in Individual Fe-filled Carbon Nanotubes

人们越来越认识到电子的自旋自由度为加强信息处理提供了机会。该材料世界网络奖支持俄亥俄州哥伦布市的俄亥俄州立大学（OSU）与德国德累斯顿莱布尼茨固体与材料研究所（IFF-IFW）的固态研究所之间的合作研究，将研究铁纳米线内的自旋输移及其内部各种界面。铁（和铜）填充的多壁碳纳米管将在德国生长和表征，美国团队将使用磁共振力显微镜（MRFM）技术研究这些结构。MRFM是一种新型的扫描探针技术，可以检测电子的磁自旋并获得纳米级分辨率的共振图像。在这个项目中，铁磁共振力显微镜（FMRFM）将应用于单个纳米线；特别是，将在单个铁磁纳米线内进行空间分辨FMR研究。这些研究将提高对纳米线的磁性，特别是阻尼特性的理解，并通过对铁磁纳米线中自旋泵浦的微观研究，加深对铁磁金属界面上自旋输运的认识。该项目还提供了一个机会来研究FMR泵浦自旋注入在铁磁纳米线的界面上。这项工作将为俄亥俄州和德国的几名研究生和一名本科生提供参与尖端纳米磁学研究的机会。本项目的主要研究者还将为本科生开设一门现代纳米磁学实验课程。铁磁纳米线具有不同寻常的磁性，非常适合用于理解纳米尺度磁性的基础研究。这些纳米线具有丰富的技术潜力，可以作为纳米级自旋电子结构的元件，也可以作为磁共振分子成像应用中的磁探针尖端。该项目结合了俄亥俄州立大学独特的铁磁共振成像能力，以及德国合作研究人员的纳米线生长和表征专业知识。研究的重点是铁填充碳纳米管，这是一种令人兴奋的新型铁磁纳米线系统。铁填充的多壁碳纳米管是一种直径为5至10纳米的结晶铁丝，包裹在一个保护性的碳纳米管外壳中。研究小组将研究纳米线内部和不同界面之间的自旋输运。这些研究将提高对磁性的理解，并加深对铁磁纳米线界面上自旋输运的认识。本项目通过交流访问的方式为多名研究生和本科生提供国际研究经验，并对他们进行现代纳米磁学相关领域的培训。这项工作得到了数学和物理科学理事会材料研究部的资助。

There is growing recognition of the opportunities offered by the spin degree of freedom of the electron to enhance information processing. This Materials World Network award, which supports collaborative research between the Ohio State University (OSU) in Columbus, OH and the Institute for Solid State Research, Leibniz Institute for Solid State and Materials Research, Dresden, Germany (IFF-IFW), will study spin transport within iron nanowires and across various interfaces within them. Iron (and copper) filled multi wall carbon nanotubes will be grown and characterized in Germany and the US team will study these structures using Magnetic Resonance Force Microscopy (MRFM) techniques. MRFM is a novel scanning probe technique that detects the magnetic spin of electrons and acquires resonance images at nanometer scale resolution. In this project, Ferromagnetic Resonance Force Microscopy (FMRFM) will be applied to individual nanowires; in particular, spatially resolved FMR studies within individual ferromagnetic nanowires will be carried out. These studies will improve understanding of magnetic properties, particularly damping, of the nanowires, and deepen insight into spin transport across interfaces with ferromagnetic metals through microscopic studies of spin pumping in ferromagnetic nanowires. The project also presents an opportunity to study FMR pumped spin injection across interfaces in ferromagnetic nanowires. This work will provide opportunities for several graduate students both in Ohio and Germany and an undergraduate student to participate in cutting edge nanomagnetics research. The prinicipal investigator on this project will also develop a course for undergraduate student laboratory in modern nanomagnetism.Ferromagnetic nanowires possess unusual magnetic properties and are well suited for fundamental studies aimed at understanding nanoscale magnetism. These nanowires have rich technological potential for use as elements in nanoscale spin-electronic structures and also as magnetic probe tips in magnetic resonance molecular imaging applications. This project combines unique ferromagnetic resonance imaging capabilities available at Ohio State University with nanowire growth and characterization expertise of collaborating researchers in Germany. The focus is on the study of iron filled carbon nanotubes, which is an exciting new ferromagnetic nanowire system. An iron filled multi wall carbon nanotube is a crystalline iron wire 5 to 10 nm in diameter encased in a protective carbon nanotube shell. The research team will study spin transport within the nanowires and across various interfaces. These studies will improve understanding of magnetic properties and deepen insight into spin transport across interfaces with ferromagnetic nanowires. The project offers international research experience for several graduate and undergraduate students through exchange visits and trains them in modern nanomagnetism related areas. This work is supported through a grant from the division of Materials Research in the Mathematical and Physical Sciences directorate.