Condensed Matter Seminar: Microfluidic Pathways towards Topological Defect Templates

Wed, 10/29/2014 - 16:00 - 18:00
Professor Anupam Sengupta, MIT

Liquid crystals (LCs) are mesogenic phases of matter which combine liquid fluidity with crystalline solid properties.The material anisotropy allows us to explore LCs as complex functional materials for microfluidics. Harnessing the anisotropic coupling between the flow and the molecular ordering renders a novel perspective to the conventional concepts in microfluidics. For instance, the topological defects emerging in the system, which are otherwise considered nuisance in applications, can be used as a self-assembled system of rails, along which micro-cargo (droplets and colloids containing the materials of interest) could be transported. Currently, we are developing tools for generating topological motifs through hydrodynamic singularities. Under appropriate flow and boundary conditions, we have been able to hierarchically tune the strength of the resulting topological defects. The results are aimed towards motivating a fundamental theoretical understanding of the coupling interactions: specifically those between the hydrodynamic and the topological singularities. We will conclude the talk with some emerging concepts in Topological Microfluidics and their possible relevance in microbial biophysics.