Non-reactive forces and pattern formation induced by a nonequilibrium medium

TL;DR

This paper investigates how nonequilibrium driven colloids induce non-reactive forces between probes, leading to stable, crystal-like patterns, with force range decreasing as driving increases.

Contribution

It reveals that nonequilibrium conditions generate non-reciprocal forces that stabilize ordered probe arrangements, a novel insight into pattern formation in driven colloidal systems.

Findings

Binary forces break action-reaction symmetry.

Force range decreases with increased driving.

Stable crystal-like probe arrangements emerge in nonlinear regimes.

Abstract

We study the induced interaction between multiple probes locally interacting with driven colloids and trapped in a toroidal geometry. The effective binary forces between the probes break the action-reaction principle and their range decreases with the driving. We demonstrate how in the stationary nonlinear nonequilibrium regime these interactions induce stability of a crystal-like pattern, where the probes are equidistant, when the probe-colloid interaction is either completely attractive or completely repulsive.