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

Ohio State University Research Foundation -Do Not Use, Columbus OH

Investigators

Abstract

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.