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Autonomously Probing Viscoelasticity in Disordered Suspensions

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 نشر من قبل Joost de Graaf
 تاريخ النشر 2020
  مجال البحث فيزياء
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Recent experiments show a strong rotational-diffusion enhancement for self-propelled microrheological probes in colloidal glasses. Here, we provide microscopic understanding using simulations with a frictional probe-medium coupling that converts active translation into rotation. Diffusive enhancement emerges from the mediums disordered structure and peaks at a second-order transition in the number of contacts. Our results reproduce the salient features of the colloidal glass experiment and support an effective description that is applicable to a broader class of viscoelastic suspensions.

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