Magnetization Directions of Individual Nanoparticles
- 16 April 1999
- journal article
- other
- Published by American Association for the Advancement of Science (AAAS) in Science
- Vol. 284 (5413), 470-473
- https://doi.org/10.1126/science.284.5413.470
Abstract
The magnetization directions of individual monodomain nanoparticles as small as 5 nanometers in diameter are determined using the Foucault method of Lorentz microscopy. A model is developed to explain the images and diffraction patterns of samarium cobalt nanoparticles as a function of the aperture shift direction. Thermally induced changes in the magnetization direction of superparamagnetic magnetite nanoparticles were observed but with a much slower rate than expected, due to surface anisotropy. When the time scale for magnetization reversal is much shorter than the data acquisition time, as in carbon-coated iron cobalt alloy nanoparticles, the images show an average of such thermally induced changes.This publication has 24 references indexed in Scilit:
- Structural Analysis of Self-Assembling Nanocrystal SuperlatticesAdvanced Materials, 1998
- Magnetic nanoparticles and magnetocrystalline anisotropyNanostructured Materials, 1997
- Thermal stability of recorded information at high densitiesIEEE Transactions on Magnetics, 1997
- Magnetization reversal in SmCo/sub 5/ nanoparticlesIEEE Transactions on Magnetics, 1997
- Surface Spin Disorder inNanoparticlesPhysical Review Letters, 1996
- Growth of High Aspect Ratio Nanometer-Scale Magnets with Chemical Vapor Deposition and Scanning Tunneling MicroscopyScience, 1993
- Observation of thermal switching of a single ferromagnetic particleJournal of Applied Physics, 1993
- Measuring the coercivity of individual sub-micron ferromagnetic particles by Lorentz microscopyIEEE Transactions on Magnetics, 1991
- Significance of Electromagnetic Potentials in the Quantum TheoryPhysical Review B, 1959
- A mechanism of magnetic hysteresis in heterogeneous alloysPhilosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences, 1948