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Direct Investigation of Superparamagnetism in Co Nanoparticle Films

S. I. Woods·J. R. Kirtley·Shouheng Sun·R. H. Koch
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Abstract

A direct probe of superparamagnetism was used to determine the complete anisotropy energy distribution of Co nanoparticle films. The films were composed of self-assembled lattices of uniform Co nanoparticles 3 nm or 5 nm in diameter, and a variable temperature scanning-SQUID microscope was used to measure temperature-induced spontaneous magnetic noise in the samples. Accurate measurements of anisotropy energy distributions of small volume samples will be critical to magnetic optimization of nanoparticle devices and media.

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S. I. Woods, J. R. Kirtley, Shouheng Sun, R. H. Koch. 2001-07-26. Direct Investigation of Superparamagnetism in Co Nanoparticle Films. https://doi.org/10.1103/physrevlett.87.137205

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