2025 AIChE Annual Meeting

(268b) Topological Flagella: Propulsion By Topological Defects in Nematic Liquid Crystals

Authors

Dr. Kathleen J. Stebe - Presenter, University of Pennsylvania
Qi Xing Zhang, University of Pennsylvania
Claire Dore, University of Pennsylvania
Mojtaba Rajabi, University of Pennsylvania
Edward Steager, University of Pennsylvania
A talk in honor of Andreas Acrivos

Rotated colloids in nematic liquid crystals generate broken symmetries in the nematic director field that drives colloid translation. In this talk, the formation of a defect wall on a rotated disk with hybrid anchoring is described. The defect wall elongates as the disk is rotated, storing elastic twist energy. At a critical angle, the defect sweeps across the face of the disk. In so doing, the stored elastic energy is released, generating a force that propels the disk motion. This motion is rationalized in terms of Leslie-Ericksen stresses.