title: Magnetic interactions of iron nanoparticles in arrays and dilute dispersions.
abstract: The magnetic properties of monodisperse Fe nanoparticles with over 4 orders of magnitude difference in concentration are studied by a combination of ordinary and remanent hysteresis loops, zero field cooled magnetization as a function of temperature, and magnetic relaxation rates. We compare the behavior of dilute dispersions with different concentrations, dispersions, and arrays made from the same particles, and nanoparticle arrays with different particle sizes and separations. The results are related to theoretical predictions and are used to create a unified picture of magnetostatic interactions within the assemblies.
authors.affiliation: Physics Department, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213-3890, USA.
authors.forename: Dorothy
authors.initials: D
authors.lastname: Farrell
authors.forename: Yuhang
authors.initials: Y
authors.lastname: Cheng
authors.forename: R William
authors.initials: RW
authors.lastname: McCallum
authors.forename: Madhur
authors.initials: M
authors.lastname: Sachan
authors.forename: Sara A
authors.initials: SA
authors.lastname: Majetich