Parts | Days | Selection | Search | Updates | Downloads | Help
DY: Fachverband Dynamik und Statistische Physik
DY 32: Poster: Active Matter, Soft Matter, Fluids
DY 32.9: Poster
Wednesday, March 20, 2024, 15:00–18:00, Poster C
Collective Hall current in chiral active fluids: Coupling of phase and mass transport through traveling bands — Frank Siebers1, •Robin Bebon2, Ashreya Jayaram2, and Thomas Speck2 — 1Institute for Theoretical Physics 4, University of Stuttgart, Heisenbergstraße 3, 70569 Stuttgart, Germany — 2Institut für Physik, Johannes Gutenberg-Universität Mainz, Staudingerweg 7-9, 55128 Mainz, Germany
Active fluids, composed of motile entities, have garnered enormous interest owing to the programmability of their collective spatiotemporal behavior that can be controlled by tuning physical properties at the individual level. We report a novel phase exhibited by locally aligning chiral particles -- (meta-)stable, dispersionless traveling bands that couple phase and mass transport. Intriguingly, the particle current is neither parallel nor perpendicular to the direction of phase propagation, with magnitudes depending on the self-propulsion and angular speeds of particles. We thus report the first instance of a self-organized Hall (or Magnus) effect in chiral active fluids with a tunable Hall angle. Through particle-based simulations, we reveal the mechanism underlying this phenomenon and corroborate our results using a minimal hydrodynamic theory. Within this framework we show that bands arise as non-dispersive soliton solutions that fully explain the properties observed in simulations.
Keywords: active matter; collective behavior; chirality; Brownian dynamics; hydrodynamic equations