A connection between Living Liquid Crystals and electrokinetic phenomena in nematic fluids

Abstract

We develop a formal analogy between configurational stresses in two distinct physical systems, and study the flows that they induce when the configurations of interest include topological de- fects. The two systems in question are electrokinetic flows in a nematic fluid under an applied electrostatic field, and the motion of self propelling or active particles in a nematic matrix (a living liquid crystal). The mapping allows the extension, within certain limits, of existing results on trans- port in electrokinetic systems to self propelled transport. We study motion induced by a pair of point defects in a dipole configuration, and steady rotating flows due to a swirling vortex nematic director pattern. The connection presented allows the design of electrokinetic experiments that correspond to particular active matter configurations that may, however, be easier to conduct and control in the laboratory.