Description of Research Area

Ordered Structure and its Control in Collective Motion of Bacteria as Active Nematics

Research Subject

The group of active matters of autonomously motile elements generates spatial-temporal structures such as wave propagation, single vortex or the lattice of vortexes. Active matters spontaneously create those patterns through velocity alignment with neighbors and hydrodynamic interactions. In this study, we investigate collective motion of dense bacterial suspension as an active matter by controlling its topological properties. We develop microfabrication method to control the direction of bacteria swimming close to a wall and find that single vortexes or the pair of vortexes is emerged in a microwell. To understand the mechanism of vortex formation, we analyze theoretical model of active nematics that connects topological property of nematic director and velocity field of fluid flow. We further study ordered structure of topological defects in order to explore universal model of active nematics.