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arXiv · 2012.10654

Autonomously Probing Viscoelasticity in Disordered Suspensions

Clara Abaurrea-Velasco·Celia Lozano·Clemens Bechinger·Joost de Graaf
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Abstract

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 medium's 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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Clara Abaurrea-Velasco, Celia Lozano, Clemens Bechinger, Joost de Graaf. 2020-12-19. Autonomously Probing Viscoelasticity in Disordered Suspensions. https://doi.org/10.1103/physrevlett.125.258002

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