Title: Dramatic growth of Dynamic and Static correlations in Active Glass-forming Liquids as probed via rod-like probe particles.

Speaker: Smarajit Karmakar (Centre for Interdisciplinary Sciences,TIFR, Hyderabad)

Abstract:

Activity driven glassy dynamics is ubiquitous in collective cell migration, intracellular transport, dynamics in bacterial and ants colonies as well as artificially driven synthetic systems such as vibrated granular materials, etc. Active glasses are hitherto assumed to be qualitatively similar to their equilibrium counterparts at a suitably defined effective temperature. Using large-scale simulations, we show that, in fact, an active glass is qualitatively different from an equilibrium glassy system. Although the relaxation dynamics can be similar to an equilibrium system at a T_eff, effects of activity on the dynamic heterogeneity (DH), which has emerged as a cornerstone of glassy dynamics, is quite nontrivial and complex. In particular, active glasses show dramatic growth of DH, and systems with similar relaxation time and can have widely varying DH. In particular, we are able to demonstrate a dramatic growth of correlation length in these systems with increasing activity which is very different compare to the passive glasses. Finally, we propose a novel method which can be implemented in experiment to measure the strong growth of dynamic heterogeneity and its associated length scale in these systems using a rod- like probe particles. If time permit, I will also discuss Stokes-Einstein and Stokes-Einstein Debye breakdown of the probe particle in these active glassy medium and their direct links to the growing dynamic heterogeneity length scale.

This event will take place in room L0.12 (lab42 building)