Physics – Condensed Matter – Soft Condensed Matter
Scientific paper
2009-11-03
Soft Matter 7, 1472-1482 (2011)
Physics
Condensed Matter
Soft Condensed Matter
Scientific paper
10.1039/C0SM00756K
We study concentrated binary colloidal suspensions, a model system which has a glass transition as the volume fraction $\phi$ of particles is increased. We use confocal microscopy to directly observe particle motion within dense samples with $\phi$ ranging from 0.4 to 0.7. Our binary mixtures have a particle diameter ratio $d_S/d_L=1/1.3$ and particle number ratio $N_S/N_L=1.56$, which are chosen to inhibit crystallization and enable long-time observations. Near the glass transition we find that particle dynamics are heterogeneous in both space and time. The most mobile particles occur in spatially localized groups. The length scales characterizing these mobile regions grow slightly as the glass transition is approached, with the largest length scales seen being $\sim 4$ small particle diameters. We also study temporal fluctuations using the dynamic susceptibility $\chi_4$, and find that the fluctuations grow as the glass transition is approached. Analysis of both spatial and temporal dynamical heterogeneity show that the smaller species play an important role in facilitating particle rearrangements. The glass transition in our sample occurs at $\phi_g \approx 0.58$, with characteristic signs of aging observed for all samples with $\phi>\phi_g$.
Desmond Kenneth W.
Franklin Scott V.
Narumi Takayuki
Tokuyama Michio
Weeks Eric R.
No associations
LandOfFree
Spatial and temporal dynamical heterogeneities approaching the binary colloidal glass transition does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Spatial and temporal dynamical heterogeneities approaching the binary colloidal glass transition, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Spatial and temporal dynamical heterogeneities approaching the binary colloidal glass transition will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-619023