Edinburgh Research Explorer

Three-dimensional imaging of colloidal glasses under steady shear

Research output: Contribution to journalArticle

Original languageEnglish
Article number028301
Pages (from-to)-
Number of pages4
JournalPhysical Review Letters
Volume99
Issue number2
DOIs
StatePublished - 13 Jul 2007

Abstract

Using fast confocal microscopy we image the three-dimensional dynamics of particles in a yielded hard-sphere colloidal glass under steady shear. The structural relaxation, observed in regions with uniform shear, is nearly isotropic but is distinctly different from that of quiescent metastable colloidal fluids. The inverse relaxation time tau(-1)(alpha) and diffusion constant D, as functions of the local shear rate (gamma) over dot, show marked shear thinning with tau(-1)(alpha)proportional to D proportional to (gamma) over dot(0.8) over more than two decades in (gamma) over dot. In contrast, the global rheology of the system displays Herschel-Bulkley behavior. We discuss the possible role of large scale shear localization and other mechanisms in generating this difference.

    Research areas

  • HIGHLY SUPERCOOLED LIQUIDS, HARD-SPHERE SUSPENSIONS, SELF-DIFFUSION, DIRECT VISUALIZATION, INDUCED ORDER, FLOW, DYNAMICS, MICROSCOPY, SOFT, HETEROGENEITIES

ID: 1413891