title: Novel aspects of magnetic interactions in a macroscopic 3D nanoparticle-based crystal.
abstract: We report magnetic measurements on a macroscopic three-dimensional fcc array of iron-oxide nanoparticles. We observe typical nanomagnetism for the randomly packed configuration of nanoparticles, including dynamical freezing and superparamagnetism. By contrast, the nanoparticle "atoms" in the fcc configuration that form the crystal exhibit a low coercivity that is weakly temperature dependent with no superparamagnetism up to 400 K.
authors.affiliation: H. H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Royal Fort, Bristol, BS8 1TL, United Kingdom.
authors.forename: O
authors.initials: O
authors.lastname: Kasyutich
authors.forename: R D
authors.initials: RD
authors.lastname: Desautels
authors.forename: B W
authors.initials: BW
authors.lastname: Southern
authors.forename: J
authors.initials: J
authors.lastname: van Lierop