title: Curvature-induced activation of a passive tracer in an active bath.
abstract: We use numerical simulations to study the motion of a large asymmetric tracer immersed in a low-density suspension of self-propelled particles in two dimensions. Specifically, we analyze how the curvature of the tracer affects its translational and rotational motion in an active environment. We find that even very small amounts of curvature are sufficient for the active bath to impart directed motion to the tracer, which results in its effective activation. We propose simple scaling arguments to characterize this induced activity in terms of the curvature of the tracer and the strength of the self-propelling force. Our results suggest new ways of controlling the transport properties of passive tracers in an active medium by carefully tailoring their geometry.
authors.affiliation: Department of Chemistry, Columbia University 3000 Broadway, New York, New York 10027, USA.
authors.forename: S A
authors.initials: SA
authors.lastname: Mallory
authors.affiliation: Departamento de Quimica Fisica, Facultad de Ciencias Quimicas, Universidad Complutense de Madrid, 28040 Madrid, Spain.
authors.forename: C
authors.initials: C
authors.lastname: Valeriani
authors.affiliation: Department of Chemistry, Columbia University 3000 Broadway, New York, New York 10027, USA.
authors.forename: A
authors.initials: A
authors.lastname: Cacciuto
mesh_terms: D008958:Models, Molecular; D008968:Molecular Conformation; D009038:Motion; D013997:Time Factors