Berlin 2024 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

BP: Fachverband Biologische Physik

BP 19: Active Matter III (joint session DY/BP/CPP)

BP 19.6: Vortrag

Mittwoch, 20. März 2024, 11:00–11:15, BH-N 334

Flow and orientational properties of active nematic liquid crystals under an electric field — •Yutaka Kinoshita and Nariya Uchida — Department of Physics, Tohoku University, Sendai, Japan

Active nematic liquid crystals are materials where each constituent has nematic symmetry and produces dipolar flow along its axis. Examples include microtubule-kinesin suspensions and actomyosin networks. Because of the input of energy into the system, the state is driven out of thermodynamic equilibrium and shows a chaotic flow called active turbulence. The flow patterns are controlled by external field, confinement, and friction. An external field induces reorientation of the active elements and suppresses chaotic flow. Here we numerically simulate the effects of an electric field on the dynamics of two-dimensional active nematics [1].

We found transitions among three states that are characterized by the degree of flow anisotropy: the active turbulence, laning state, and uniformly aligned state. The average flow speed and its anisotropy are maximized in the laning state. We also found localization of vortices and topological defects associated with periodic shifts between active turbulence and laning state, which is similar to experimentally observed oscillations in a friction-controlled system. Our results might lead to a further understanding of the dynamical states of active nematics under an external field.

[1] Y. Kinoshita and N. Uchida, Phys. Rev. E 108, 014605 (2023)

Keywords: Active nematics; Flow pattern; Electric field