Model for the easy-axis alignment of chemically synthesized L10 FePt nanoparticles -: art. no. 202508

Analytical and computational models of the easy-axis orientation process in magnetic nanoparticle systems are investigated and compared with experimental data. The computational model gives good agreement with experiment on the assumption of a reduced anisotropy constant, which is ascribed to the existence of aggregation. It is found that the degree of orientation depends on the parameter KV/kT, with K the anisotropy constant and V the nanoparticle volume, which governs the coupling of the easy axis to the magnetic moment. A simple and useful analytical expression is derived, from which the primary conditions for good alignment are determined. (C) 2005 American Institute of Physics.