Field-Particle Interactions in Curved Flows for Shape-Asymmetric Active Particles

TL;DR

This paper explores how curvature in flow profiles influences the orientation and behavior of shape-asymmetric active particles in microchannels, revealing new control mechanisms and potential applications in active matter systems.

Contribution

It uncovers the competition between flow-induced alignment and external fields in curved flows, and analyzes its effects on active particle dynamics in microchannels.

Findings

Flow curvature can align active particles contrary to external fields.

The interplay leads to novel control mechanisms for particle behavior.

Potential applications include active-particle analogs of electronic systems.

Abstract

We show that curvatures in general ambient flow profiles can align shape-asymmetric active particles, revealing a previously overlooked competition with externally applied aligning fields. Focusing on the ubiquitous case of channel flows, we then investigate the fundamental consequences of this competition for the dynamics of shape-asymmetric active particles in microchannels in the presence of orienting fields. We find that this interplay gives rise to novel mechanisms for controlling particle dynamics, with potentially broad applications, and suggests exciting possibilities such as active-particle analogs of electronic systems.