title: Using symmetry breaking for directed transport of paramagnetic colloids on garnet films.
abstract: The transport behavior of paramagnetic particles on top of a ferrimagnetic garnet film is investigated in a modulated external magnetic field. Broken symmetries are required to direct the transport of the particles. We provide such symmetry breaking by tilting the external field modulation with respect to the normal direction of the garnet film and by the intrinsic geometrical symmetry breaking of the garnet film magnetic pattern. The interplay of both symmetry breaking mechanisms causes a rich variety in transport behavior and direction. We corroborate our experimental transport directions by comparing experimental with theoretical transport phase diagrams. Directing the transport of paramagnetic colloids will be useful when they are loaded with biomedical cargo on a magnetic lab-on-a-chip device.
authors.affiliation: Institut für Experimentalphysik, Universität Bayreuth, 95440 Bayreuth, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Aliaskarisohi
authors.forename: T H
authors.initials: TH
authors.lastname: Johansen
authors.forename: Th M
authors.initials: TM
authors.lastname: Fischer