Direct Investigation of Superparamagnetism in Co Nanoparticle Films

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.

arXiv comment4 pages, 4 figures. Submitted to Physical Review Letters

References in corpus (1)

• Magnetic Anisotropy of a Single Cobalt Nanoparticle

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