A collective dynamics description of dipolar interactions and the coercive field of magnetic nanoparticles
نویسندگان
چکیده
The effect of dipolar interactions on the coercive field of Ni nanoparticles embedded as layers in a Al2O3 host matrix is discussed. The results for two sets of 5 layer samples with different interlayer spacings and a set of single layer samples are compared for samples with particle size varying from 3 nm single domain to 60 nm multiple domain . The dipolar interactions are strongest in the samples with shorter interlayer distances and weakest for the single layer samples. Our observation that dipolar interactions increase the coercive field and decrease the critical diameter separating single domain from multiple domain behavior reinforces a description based on collective dynamics. © 2010 American Institute of Physics. doi:10.1063/1.3524277
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