title: Regulating wave front dynamics from the strongly discrete to the continuum limit in magnetically driven colloidal systems.
abstract: The emergence of wave fronts in dissipative driven systems is a fascinating phenomenon which can be found in a broad range of physical and biological disciplines. Here we report the direct experimental observation of discrete fronts propagating along chains of paramagnetic colloidal particles, the latter propelled above a traveling wave potential generated by a structured magnetic substrate. We develop a rigorously reduced theoretical framework and describe the dynamics of the system in terms of a generalized one-dimensional dissipative Frenkel-Kontorova model. The front dynamics is explored in a wide range of field parameters close to and far from depinning, where the discrete and continuum limits apply. We show how symmetry breaking and finite size of chains are used to control the direction of front propagation, a universal feature relevant to different systems and important for real applications.
authors.affiliation: Estructura i Constituents de la Matèria, Universitat de Barcelona, Av. Diagonal 647, 08028, Barcelona, Spain.
authors.forename: Fernando
authors.initials: F
authors.lastname: Martinez-Pedrero
authors.affiliation: Estructura i Constituents de la Matèria, Universitat de Barcelona, Av. Diagonal 647, 08028, Barcelona, Spain.|Institut de Nanociència i Nanotecnologia, Universitat de Barcelona, Barcelona, Spain.
authors.forename: Pietro
authors.initials: P
authors.lastname: Tierno
authors.affiliation: Department of Physics, The University of Oslo, P.O. Box 1048 Blindern, 0316 Oslo, Norway.|Institute for Superconducting and Electronic Materials, University of Wollongong Innovation Campus, Squires Way, North Wollongong NSW 2500, Australia.
authors.forename: Tom H
authors.initials: TH
authors.lastname: Johansen
authors.affiliation: Department of Physics, Humboldt-Universität zu Berlin, Newtonstr. 15, D-12489 Berlin, Germany.
authors.forename: Arthur V
authors.initials: AV
authors.lastname: Straube
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