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Published on: November 10, 2014
Topological protection of multiparticle dissipative transport
Johannes Loehr1, Michael Loenne2, Adrian Ernst3
1Experimentalphysik, Institutes of Physics and Mathematics, Universität Bayreuth, Universitätsstraβe 30, Bayreuth 95440, Germany.
Abstract:
Topological protection allows robust transport of localized phenomena such as quantum information, solitons and dislocations. The transport can be either dissipative or non-dissipative. Here, we experimentally demonstrate and theoretically explain the topologically protected dissipative motion of colloidal particles above a periodic hexagonal magnetic pattern. By driving the system with periodic modulation loops of an external and spatially homogeneous magnetic field, we achieve total control over the motion of diamagnetic and paramagnetic colloids. We can transport simultaneously and independently each type of colloid along any of the six crystallographic directions of the pattern via adiabatic or deterministic ratchet motion. Both types of motion are topologically protected. As an application, we implement an automatic topologically protected quality control of a chemical reaction between functionalized colloids. Our results are relevant to other systems with the same symmetry.
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