title: Interfacial mechanisms in active emulsions.
abstract: Active emulsions, i.e., emulsions whose droplets perform self-propelled motion, are of tremendous interest for mimicking collective phenomena in biological populations such as phytoplankton and bacterial colonies, but also for experimentally studying rheology, pattern formation, and phase transitions in systems far from thermal equilibrium. For fuelling such systems, molecular processes involving the surfactants which stabilize the emulsions are a straightforward concept. We outline and compare two different types of reactions, one which chemically modifies the surfactant molecules, the other which transfers them into a different colloidal state. While in the first case symmetry breaking follows a standard linear instability, the second case turns out to be more complex. Depending on the dissolution pathway, there is either an intrinsically nonlinear instability, or no symmetry breaking at all (and hence no locomotion).
authors.affiliation: Max-Planck Institute for Dynamics and Self-Organization, Göttingen, Germany. stephan.herminghaus@ds.mpg.de.
authors.forename: Stephan
authors.initials: S
authors.lastname: Herminghaus
authors.forename: Corinna C
authors.initials: CC
authors.lastname: Maass
authors.forename: Carsten
authors.initials: C
authors.lastname: Krüger
authors.forename: Shashi
authors.initials: S
authors.lastname: Thutupalli
authors.forename: Lucas
authors.initials: L
authors.lastname: Goehring
authors.forename: Christian
authors.initials: C
authors.lastname: Bahr
mesh_terms: D000327:Adsorption; D003102:Colloids / Q000737:chemistry*; D004655:Emulsions / Q000737:chemistry*; D008422:Materials Testing; D008823:Micelles; D009068:Movement; D009991:Oscillometry; D044367:Phase Transition; D010839:Phytoplankton; D012212:Rheology; D013499:Surface Properties; D013501:Surface-Active Agents / Q000737:chemistry*; D014867:Water / Q000737:chemistry
chemical_list: D003102:Colloids; D004655:Emulsions; D008823:Micelles; D013501:Surface-Active Agents; D014867:Water