Driven probe under harmonic confinement in a colloidal bath

Vincent Démery; Étienne Fodor

doi:10.1088/1742-5468/ab02e9

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arXiv · 1811.09472

Driven probe under harmonic confinement in a colloidal bath

Vincent Démery·Étienne Fodor

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Abstract

Colloids held by optical or magnetic tweezers have been used to explore the local rheological properties of a complex medium and to extract work from fluctuations with some appropriate protocols. However, a general theoretical understanding of the interplay between the confinement and the interaction with the environment is still lacking. Here, we explore the statistical properties of the position of a probe confined in a harmonic trap moving at constant velocity and interacting with a bath of colloidal particles maintained at a different temperature. Interactions among particles are accounted for by a systematic perturbation, whose range of validity is tested against direct simulations of the full dynamics. Overall, our results provide a way to predict the effect of the driving and the environment on the probe, and can potentially be used to investigate the properties of colloidal heat engines with many-body interactions.

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BibTeX RIS

Vincent Démery, Étienne Fodor. 2019-01-14. Driven probe under harmonic confinement in a colloidal bath. https://doi.org/10.1088/1742-5468%2Fab02e9

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