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Observation of strongly heterogeneous dynamics at the depinning transition in a colloidal glass

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 نشر من قبل Frank Scheffold
 تاريخ النشر 2018
  مجال البحث فيزياء
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We study experimentally the origin of heterogeneous dynamics in strongly driven glass-forming systems. Thereto, we apply a well-defined force with a laser line trap on individual colloidal polystyrene probe particles seeded in an emulsion glass composed of droplets of the same size. Fluid and glass states can be probed. We monitor the trajectories of the probe and measure displacements and their distributions. Our experiments reveal intermittent dynamics around a depinning transition at a threshold force. For smaller forces, linear response connects mean displacement and quiescent mean squared displacement. Mode coupling theory calculations rationalize the observations.



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