title: Pattern formation in chemically interacting active rotors with self-propulsion.
abstract: We demonstrate that active rotations in chemically signalling particles, such as autochemotactic E. coli close to walls, create a route for pattern formation based on a nonlinear yet deterministic instability mechanism. For slow rotations, we find a transient persistence of the uniform state, followed by a sudden formation of clusters contingent on locking of the average propulsion direction by chemotaxis. These clusters coarsen, which results in phase separation into a dense and a dilute region. Faster rotations arrest phase separation leading to a global travelling wave of rotors with synchronized roto-translational motion. Our results elucidate the physics resulting from the competition of two generic paradigms in active matter, chemotaxis and active rotations, and show that the latter provides a tool to design programmable self-assembly of active matter, for example to control coarsening.
authors.affiliation: SUPA, School of Physics and Astronomy, University of Edinburgh, Edinburgh EH9 3FD, UK. Benno.Liebchen@staffmail.ed.ac.uk.
authors.forename: Benno
authors.initials: B
authors.lastname: Liebchen
authors.forename: Michael E
authors.initials: ME
authors.lastname: Cates
authors.forename: Davide
authors.initials: D
authors.lastname: Marenduzzo