Rui Zhang, University of Chicago
601, Pao Yue-Kong Library
Topological defects in liquid crystals exhibit unique optical and physicochemical properties that have led to emerging applications in directed self-assembly of colloids and macromolecules. Recent experiments have demonstrated that dense suspensions of self-propelled particles can become an active nematic liquid crystal in which defects bind and unbind in a chaotic-like manner. Abundant examples of active nematics are found in various animate and inanimate systems, including animal flocks, bacteria, cytoskeletal polymer suspensions, and vibrating granular rods. However, the material properties and seemingly chaotic-like dynamics of defects in these non-equilibrium systems are poorly understood, limiting its further applications. In this talk, I will discuss our recent work on unraveling defect behavior in active nematics. Specifically, we have adopted a hydrodynamic model to explain how the structure and dynamics of defects are determined by the interplay between elasticity and activity. Successfully confirmed by actin-based experiments, our simulations shed light on understanding and further control of topological defects in active liquid crystals.