Introduction

Understanding the out-of-equilibrium properties of noisy microscale systems and the extent to which they can be modulated externally, is a crucial scientific and technological challenge. It holds the promise to unlock disruptive new technologies ranging from targeted delivery of chemicals within the body to directed assembly of new materials. Here we focus on how active matter can be harnessed to transport passive microscopic systems in a statistically predictable way. Using a minimal active-passive system of weakly Brownian particles and swimming microalgae, we show that spatial confinement leads to a complex non-monotonic steady-state distribution of colloids, with a pronounced peak at the boundary. The particles’ emergent active dynamics is well captured by a space-dependent Poisson process resulting from the space-dependent motion of the algae. The space-dependence of this dynamics and the resulting particle distribution can be modified by changing the interaction of the active elements with the confining walls. Based on our findings, we then realise experimentally the de-mixing of the active-passive suspension, opening the way for manipulating colloidal objects via controlled activity fields.

 

Speakers

• Dr Marco Polin Mediterranean Institute for Advanced Studies IMEDEA UIB-CSI, Spain

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Venue

United Kingdom

Committee

• Dr Charlie Wand University of Exeter, United Kingdom
• Professor Andrew Masters University of Manchester, United Kingdom
• Dr Davide Michieletto University of Edinburgh, United Kingdom

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Contact information

Charlie Wand
Contact us by email

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