title: Magnetic field induced assembly of highly ordered two-dimensional particle arrays.
abstract: Suspended magnetic beads are exposed to an external homogeneous magnetic field which rotates around the axis perpendicular to the field direction. Because of dipolar interactions, magnetic beads assemble in highly ordered two-dimensional hexagonal arrays perpendicular to the rotation axis. By continuous provision of the particle concentration, the growth modes of two-dimensional particle clusters and monolayers are observed. The structure of the resulting assembled objects is analyzed for different field frequencies and particle concentrations. We identify dynamic processes which enhance stability and reduce lattice distortions and, thus, allow for the application of these particle agglomerations as dynamic components in lab-on-a-chip technologies.
authors.affiliation: Department of Physics, Thin Films and Physics of Nanostructures, Bielefeld University, PB 100131, 33501 Bielefeld, Germany. weddeman@physik.uni-bielefeld.de
authors.forename: Alexander
authors.initials: A
authors.lastname: Weddemann
authors.forename: Frank
authors.initials: F
authors.lastname: Wittbracht
authors.forename: Bernhard
authors.initials: B
authors.lastname: Eickenberg
authors.forename: Andreas
authors.initials: A
authors.lastname: Hütten