Magnetic anisotropy of non-interacting collinear nanocrystal-chains

The magnetic anisotropy of linear chains of spherical magnetite nanocrystals was investigated by means of angle-resolved ferromagnetic resonance spectroscopy, in order to determine the different anisotropy contributions. The linear assembly of nanocrystals generates an interaction-induced uniaxial anisotropy, which is nearly an order of magnitude stronger than the intrinsic magnetocrystalline anisotropy of magnetite, and can only exist in magnetic nano-chains, where the easy axes of the nanocrystals are collinear. (C) 2014 AIP Publishing LLC.