Colloidal phoresis in odd fluids

TL;DR

This paper demonstrates the existence of odd phoresis, where colloidal particles in odd fluids migrate perpendicular to thermodynamic gradients, supported by mesoscale simulations and flow field analysis.

Contribution

It introduces the concept of odd diffusiophoresis and thermophoresis in colloids within odd fluids through simulation and flow field characterization.

Findings

Colloidal particles exhibit perpendicular migration in odd fluids.

Flow fields driven by diffusiophoretic forces match fluid dynamics simulations.

Abstract

Under a thermodynamic gradient, for example, the concentration or temperature gradients, the colloidal particles immersed in the solvent can exhibit a directional migration along or against the gradient -- phoresis, a cross transport effect. When the solvent is an odd fluid, where the time-reversal and parity symmetries are broken microscopically, the odd transport phenomenon is allowed. This means an odd phoresis may appear: the colloidal particle migrates perpendicularly to the thermodynamic gradient. Here, we realize the odd diffusiophoresis and odd thermophoresis for a colloidal particle immersed in a two-dimensional odd fluid by performing mesoscale fluid simulations. We further provide the flow field driven by the diffusiophoretic force, which is quantitatively consistent with the numerical solutions of the corresponding odd fluid dynamics equations.