Defects and flow in active nematic systems
By: Sumesh Thampi
From: University of Oxford
At: Instituto de Investigação Interdisciplinar, Anfiteatro
[2013-11-13]
The flow properties of a continuum model for an active nematic is studied and compared with recent experiments on suspensions of microtubule bundles and molecular motors. The velocity correlation length is found to be independent of the strength of the activity while the characteristic velocity scale increases monotonically as the activity is increased, both in agreement with the experimental observations. We argue that the length scale is set by the dynamics of topological defects. We also show the difference in behaviour of extensile and contractile systems in terms of defect creation and annihilation mechanisms.