Spatiotemporal dynamics of short- and long-time structural relaxation are measured experimentally as a function of packing fraction, φ, in quasi-two-dimensional colloidal supercooled liquids and glasses. The relaxation times associated with long-time dynamic heterogeneity and short-time intracage motion are found to be strongly correlated and to grow by orders of magnitude with increasing φ toward dynamic arrest. We find that clusters of fast particles on the two timescales often overlap, and, interestingly, the distribution of minimum-spatial-separation between closest nonoverlapping clusters across the two timescales is revealed to be exponential with a decay length that increases with φ. In total, the experimental observations suggest short-time relaxation events are very often precursors to heterogeneous relaxation at longer timescales in glassy materials.
Physical Review E
American Physical Society
Mishra, C. K., Ma, X., Habdas, P., Aptowicz, K. B., & Yodh, A. G. (2019). Correlations between short- and long-time relaxation in colloidal supercooled liquids and glasses. Physical Review E, 100(2), 020603-1-020603-5. http://dx.doi.org/10.1103/PhysRevE.100.020603