The order-disorder transition in colloidal suspensions under shear flow

TL;DR

This study investigates how shear flow influences the order-disorder transition in colloidal suspensions using Brownian dynamics simulations, revealing distinct spectral behaviors in different phases.

Contribution

It introduces a novel analysis of the transition based on the structure factor's maximum value and its power spectrum, highlighting phase-dependent spectral characteristics.

Findings

Power-law behavior in the power spectrum appears only in the ordered phase.

The power-law exponent is approximately -2 at high frequencies.

The spectrum shows 1/f-type fluctuations at low frequencies.

Abstract

We study the order-disorder transition in colloidal suspensions under shear flow by performing Brownian dynamics simulations. We characterize the transition in terms of a statistical property of time-dependent maximum value of the structure factor. We find that its power spectrum exhibits the power-law behaviour only in the ordered phase. The power-law exponent is approximately -2 at frequencies greater than the magnitude of the shear rate, while the power spectrum exhibits the $1 / f$-type fluctuations in the lower frequency regime.