Hydrodynamic interactions in active colloidal crystal microrheology

TL;DR

This paper investigates how hydrodynamic interactions influence defect formation, crystal regeneration, and jamming in dense colloidal crystals, using simulations that incorporate long-range hydrodynamics for more accurate modeling.

Contribution

It introduces an improved simulation scheme that includes limited hydrodynamic interactions, revealing their significant impact on colloidal crystal behavior.

Findings

Hydrodynamics strongly affect defect development.

Hydrodynamics influence crystal regeneration.

Hydrodynamics impact jamming behavior.

Abstract

In dense colloids it is commonly assumed that hydrodynamic interactions do not play a role. However, a found theoretical quantification is often missing. We present computer simulations that are motivated by experiments where a large colloidal particle is dragged through a colloidal crystal. To qualify the influence of long-ranged hydrodynamics, we model the setup by conventional Langevin dynamics simulations and by an improved scheme with limited hydrodynamic interactions. This scheme significantly improves our results and allows to show that hydrodynamics strongly impacts on the development of defects, the crystal regeneration as well as on the jamming behavior.