Self-Starting Micromotors in a Bacterial Bath

TL;DR

This paper demonstrates through simulations that asymmetric microobjects can spontaneously move in a bacterial bath, showcasing a new way to harness bacterial activity for microdevice propulsion and illustrating how active matter differs from thermal systems.

Contribution

It introduces a novel design principle for self-starting micromotors driven by bacterial baths, highlighting the rectification of active particle motion via asymmetry.

Findings

Asymmetric objects spontaneously move in bacterial baths.

Active matter motion can be rectified by asymmetric environments.

Potential for designing hybrid microdevices using bacteria.

Abstract

Micromotors pushed by biological entities, like motile bacteria, constitute a fascinating way to convert chemical energy into mechanical work at the micrometer scale. Here we show, by using numerical simulations, that a properly designed asymmetric object can be spontaneously set into the desired motion when immersed in a chaotic bacterial bath. Our findings open the way to conceive new hybrid microdevices exploiting the mechanical power production of bacterial organisms. Moreover, the system provides an example of how, in contrast with equilibrium thermal baths, the irreversible chaotic motion of active particles can be rectified by asymmetric environments.