Straube, Arthur V.Pagès Casas, Josep M.Ortiz-Ambriz, AntonioTierno, PietroIgnés i Mullol, JordiSagués i Mestre, Francesc2019-02-042019-02-042018-07-181367-2630https://hdl.handle.net/2445/127850We investigate the dynamic assembly and swarm translocation of anisometric colloidal particles dispersed in a nematic liquid crystal and driven above a photosensitive surface. We use liquid crystal-enabled electrophoresis to propel these particles via an alternating electric field perpendicular to the sample cell. By manipulating the anchoring conditions on one surface of the experimental cell, we obtain a spatially extended spiral pattern of the liquid crystal orientation that induces the dynamic assembly of a rotating colloidal mill. This structure can be transported by translocating the topological defect above the photosensitive surface. We complement our findings with a theoretical model that captures the basic physics of the process, by formulating an analytic equation for the director field above the surface. Our reconfigurable nematic assemblies may be used as a test bed for complex swarming behaviour in biological and artificial microscale systems.application/pdfeng(c) IOP Publishing Ltd and Deutsche Physikalische Gesellschaft, 2018Col·loidesCristalls líquidsColloidsLiquid crystalsAssembly and transport of nematic colloidal swarms above photo-patterned defects and surfacesinfo:eu-repo/semantics/article6829952019-02-04info:eu-repo/semantics/openAccess