SKM 2023 – wissenschaftliches Programm
DY 3.10: Vortrag
Montag, 27. März 2023, 12:15–12:30, TOE 317
Interacting particles in an activity landscape — •Adam Wysocki1, Anil Kumar Dasanna1,2, and Heiko Rieger1,2 — 1Department of Theoretical Physics and Center for Biophysics, Saarland University, Saarbrücken, Germany — 2INM-Leibniz Institute for New Materials, Saarbrücken, Germany
We study interacting active Brownian particles (ABPs) with a space-dependent swim velocity. We find that, although an equation of state exists, a mechanical equilibrium does not apply to ABPs in activity landscapes. The pressure imbalance originates in the flux of polar order across the interface between regions of different activity. An active-passive patch system is mainly controlled by the smallest global density for which the passive patch can be close packed. Below this density a critical point does not exist and the system splits continuously into a dense passive and a dilute active phase with increasing activity. Above this density and for sufficiently high activity the active phase may start to phase separate into a gas and a liquid phase caused by the same mechanism as motility-induced phase separation of ABPs with a homogeneous swim velocity.