Die DPG-Frühjahrstagung in Dresden musste abgesagt werden! Lesen Sie mehr ...

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

DY: Fachverband Dynamik und Statistische Physik

DY 42: Fluid Physics of Life (joint session DY/BP)

DY 42.6: Vortrag

Mittwoch, 18. März 2020, 16:45–17:00, ZEU 160

Artificial topological defects organize bacterial motion — •Henning Reinken¹, Sebastian Heidenreich², Daiki Nishiguchi³, Andrey Sokolov⁴, Igor Aranson⁵, Markus Bär², and Sabine Klapp¹ — ¹Technische Universität Berlin — ²Physikalisch-Technische Bundesanstalt Berlin — ³University of Tokyo, Japan — ⁴Argonne National Laboratory, USA — ⁵Pennsylvania State University, USA

Active systems spontaneously self-organize into complex spatio-temporal structures such as flocks, bands, vortices, and turbulence. These collective states are susceptible to weak geometrical confinement, as has been demonstrated in experiments on suspensions of Bacillus subtilis, where turbulent motion is organized into a highly ordered bacterial vortex lattice by arrays of tiny obstacles [1].
Using a continuum-theoretical approach [2], we show how self-induced topological defects imposed by artificial obstacles guide the flow profile of the active fluid and enable the stabilization of vortex patterns with tunable properties. Beyond the stabilization of square and hexagonal lattices, we also provide a striking example of a chiral, antiferromagnetic lattice induced by arranging the obstacles in a Kagome-like array. In this setup, the interplay of lattice topology, activity and length-scale selection generates a net rotational flow. Further, we investigate how the properties of the stabilized patterns impact the transport of tracer particles in the active fluid.
[1] D. Nishiguchi et al., Nat. Commun. 9, 4486 (2018).
[2] H. Reinken et al., Phys. Rev. E 97, 022613 (2018).