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Download or read book Nanoscale Ferromagnetic Resonance Imaging Using Magnetic Resonance Force Microscopy written by Inhee Lee and published by . This book was released on 2010 with total page 186 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Nanoscale patterned magnetic structures and multi-component magnetic devices have been studied actively for applications of highly efficient data storage and non-volatile magnetic memory devices. Those studies demand high resolution magnetic imaging tools which can characterize complex, often buried nanoscale structures. Ferromagnetic Resonance (FMR) is a powerful spectroscopic tool which provides the magnetic characterizing parameters of spectroscopically identified magnetic materials with high precision. However, FMR studies of nanoscale samples are limited due to insufficient sensitivity and lack of imaging capabilities. Scanned probe FMR using Magnetic Resonance Force Microscopy (MRFM) is an excellent tool for understanding nanoscale ferromagnetic structures based on its high sensitivity and high resolution. Non-interacting electron and nuclear spins in MRFM can be excited selectively in the thin sensitive slice defined by the high magnetic field gradient of the magnetic probe tip. The sensitive slice as a probe enables high resolution three-dimensional imaging. However, for ferromagnets, the mechanism for magnetic resonance imaging is quite different due to the strong spin-spin interactions which lead to collective spin wave excitation. Our recent studies of Ferromagnetic Resonance Force Microscopy (FMRFM) have shown that the magnetic probe tip not only detects the FMRFM force, but also perturbs FMR modes, and even distorts or spatially localizes FMR modes using the strongly inhomogeneous probe field. This strong perturbation of probe field enables us to achieve and image quantitative magnetic information in the local region of ferromagnetic structures. In this thesis I will present various FMRFM imaging techniques using the strong inhomogeneous magnetic field of the micromagnetic probe tip. First, FMRFM imaging in a weak probe field will be discussed. In this case, the shapes of magnetostatic modes in FMR are determined by a confined sample structure while the effect of probe field is ignorable. However, FMR peak positions are shifted by the probe field, which allows encoding of the spatial mode profile of magnetostatic modes into FMR resonance field. On the other hand, in a strong probe field, the shapes of FMR modes can be distorted or spatially localized. In particular, localized modes are suitable for FMRFM imaging which provides a map of intrinsic magnetic properties existing within the local area of the sample. Concerning these localized modes, I will present our recent observations, quantitative analysis and their application for FMR imaging with high field sensitivity of the internal field in a ferromagnetic film . Furthermore, I will discuss other quantitative local magnetic characterization methods such as magnetic force microscopy (MFM) induced by a strong inhomogeneous probe tip field and suppressed or distorted FMR modes FMRFM.