# Mixing by Unstirring: Hyperuniform Dispersion of Interacting Particles upon Chaotic Advection

## TL;DR

This paper introduces a method to achieve rapid, uniform particle dispersions in viscous fluids by designing specific stirring sequences that leverage chaotic advection to prevent self-organization and promote hyperuniformity.

## Contribution

It extends the concept of critical random organization to chaotic drives and designs stirring sequences that optimize both dispersion speed and uniformity.

## Key findings

- Palindromic sequences of chaotic advection inhibit critical self-organization.
- Designed stirring sequences achieve hyperuniform dispersions.
- Method improves both speed and homogeneity of particle dispersion.

## Abstract

We show how to achieve both fast and hyperuniform dispersions of particles in viscous fluids. To do so, we first extend the concept of critical random organization to chaotic drives. We show how palindromic sequences of chaotic advection cause microscopic particles to effectively interact at long range thereby inhibiting critical self-organization. Based on this understanding we go around this limitation and design sequences of stirring and unstirring which simultaneously optimize the speed of particle spreading and the homogeneity of the resulting dispersions.