Abstract
Thermomagnetic measurements are used to obtain the size distribution and anisotropy of magnetic nanoparticles. An analytical transformation method is described which utilizes temperature-dependent zero-field cooling magnetization data to provide a quantitative measurement of the average diameter and relative abundance of superparamagnetic nanoparticles. Applying this method to self-assembled MnAs nanoparticles in MnAs–GaAs composite films reveals a log-normal size distribution and reduced anisotropy for nanoparticles compared to bulk materials. This analytical technique holds promise for rapid assessment of the size distribution of an ensemble of superparamagnetic nanoparticles.
Keywords
III-V semiconductors, magnetic anisotropy, magnetic moments, magnetic particles, nanofabrication, superparamagnetism
Subject Categories
Gallium arsenide, Anisotropy, Manganese Compounds, Nanocomposites (Materials), Nanoparticles
Disciplines
Physics
Publisher
American Institute of Physics
Publication Date
6-3-2010
Rights Information
© 2010 American Institute of Physics
Rights Holder
American Institute of Physics
Permanent URL
Recommended Citation
DiPietro, R. S.; Johnson, H. G.; Bennett, S. P.; Nummy, T. J.; Lewis, L. H.; and Heiman, D., "Determining magnetic nanoparticle size distributions from thermomagnetic measurements." (2010). Physics Faculty Publications. Paper 179. http://hdl.handle.net/2047/d20001190
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Additional Files
fig1.zip (27 kB)Figure 1
fig2.zip (194 kB)
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fig3.zip (40 kB)
Figure 3
Notes
Published in: Applied Physics Letters 96, 222506 (2010); doi:10.1063/1.3441411