Power-law intermittency in the gradient-induced self-propulsion of colloidal swimmers

Nick Oikonomeas-Koppasis; Stefania Ketzetzi; Daniela J. Kraft; Peter Schall

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arXiv · 2310.17384

Power-law intermittency in the gradient-induced self-propulsion of colloidal swimmers

Nick Oikonomeas-Koppasis·Stefania Ketzetzi·Daniela J. Kraft·Peter Schall

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Abstract

Active colloidal microswimmers serve as archetypical active fluid systems, and as models for biological swimmers. Here, by studying in detail their velocity traces, we find robust power-law intermittency with system-dependent exponential cut off. We model the motion by an interplay of the field gradient-dependent active force and the locally fluctuating hydrodynamic drag, set by the wetting properties of the substrate. The model closely describes the velocity distributions of two disparate swimmer systems: AC field activated and catalytic swimmers. The generality is highlighted by the collapse of all data in a single master curve, suggesting the applicability to further systems, both synthetic and biological.

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Nick Oikonomeas-Koppasis, Stefania Ketzetzi, Daniela J. Kraft, Peter Schall. 2023-10-26. Power-law intermittency in the gradient-induced self-propulsion of colloidal swimmers. https://arxiv.org/abs/2310.17384

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