title: Dipolar-interaction-induced fractal pattern formation in magnetic multilayers.
abstract: Models concerning particle diffusion and aggregation have been proposed for decades, and the aggregations with long-range dipolar interaction are simulated and analyzed numerically. In this paper, fractal clusters composed of particles diffusing with dipolar interaction are observed, and a model taking both magnetic force and diffusion activation energy into account is presented. The computer-simulation results generate clusters similar to those observed. And the measured sizes and dimensions of the experimental results are close to that of simulation. Further investigations on the magnetic energy and cluster size reveal that the dipolar interaction and thermal disruption play significant roles in the aggregation of nanosize magnetic particles and the interaction energy is the main driving force of the formation of the ordered structure.
authors.affiliation: Laboratory of Advanced Materials, Department of Materials Science and Engineering, Tsinghua University, Beijing 100084, People's Republic of China.
authors.forename: F
authors.initials: F
authors.lastname: Yang
authors.forename: F
authors.initials: F
authors.lastname: Pan