Length scale dependence of dynamical heterogeneity in a colloidal fractal gel
| dc.creator | Duri, Agnes | |
| dc.creator | Cipelletti, Luca | |
| dc.date | 2006-06-02 | |
| dc.date | 2006-10-20 | |
| dc.date.accessioned | 2026-07-07T07:12:22Z | |
| dc.date.available | 2026-07-07T07:12:22Z | |
| dc.description | We use time-resolved dynamic light scattering to investigate the slow dynamics of a colloidal gel. The final decay of the average intensity autocorrelation function is well described by $g\_2(q,τ)-1 \sim \exp[-(τ/τ\_\mathrm{f})^p]$, with $τ\_\mathrm{f} \sim q^{-1}$ and $p$ decreasing from 1.5 to 1 with increasing $q$. We show that the dynamics is not due to a continuous ballistic process, as proposed in previous works, but rather to rare, intermittent rearrangements. We quantify the dynamical fluctuations resulting from intermittency by means of the variance $χ(τ,q)$ of the instantaneous autocorrelation function, the analogous of the dynamical susceptibility $χ\_4$ studied in glass formers. The amplitude of $χ$ is found to grow linearly with $q$. We propose a simple --yet general-- model of intermittent dynamics that accounts for the $q$ dependence of both the average correlation functions and $χ$. | |
| dc.description | Revised and improved, to appear in Europhys. Lett | |
| dc.identifier | https://arxiv.org/abs/cond-mat/0606051 | |
| dc.identifier | http://arxiv.org/abs/cond-mat/0606051 | |
| dc.identifier | Europhysics Letters 76 (2006-12-01) 972 | |
| dc.identifier | doi:10.1209/epl/i2006-10357-4 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/112060 | |
| dc.subject | Soft Condensed Matter | |
| dc.title | Length scale dependence of dynamical heterogeneity in a colloidal fractal gel | |
| dc.type | text |