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.
| Original language | English |
|---|---|
| Article number | 258002 |
| Journal | Physical Review Letters |
| Volume | 125 |
| Issue number | 25 |
| DOIs | |
| Publication status | Published - 18 Dec 2020 |
Funding
J. d G. gratefully recognizes the Dutch Research Council (NWO) for funding this research through Start-Up Grant No. 740.018.013. C. B. acknowledges financial support by the ERC Advanced Grant ASCIR (Grant No. 693683) and by the German Research Foundation (DFG) through the priority programme SPP 1726. We thank F. Smallenburg, M. Hermes, and L. Filion for useful discussions. Conceptualization, J. d G.; methodology, C. A. V., C. L., C. B., and J. d G.; software, C. A. V.; validation, C. A. V. (lead) and C. L. and J. d G. (supporting); investigation, C. A. V. (lead) and C. L. (supporting); original draft, C. A. V. and J. d G.; review and editing, J. d G., C. B., C. A. V., and C. L.; funding acquisition, resources, and supervision, J. d G. and C. B.