Asymmetric fluctuations and self-folding of active interfaces

Journal Article · Mon Dec 09 19:00:00 EST 2024 · Proceedings of the National Academy of Sciences of the United States of America

DOI: https://doi.org/10.1073/pnas.2410345121 · OSTI ID:2480745

Zhao, Liang ; Gulati, Paarth ; Caballero, Fernando ; Kolvin, Itamar ; Adkins, Raymond ; Marchetti, M. Cristina ; Dogic, Zvonimir

We study the structure and dynamics of the interface separating a passive fluid from a microtubule-based active fluid. Turbulent-like active flows power giant interfacial fluctuations, which exhibit pronounced asymmetry between regions of positive and negative curvature. Experiments, numerical simulations, and theoretical arguments reveal how the interface breaks up the spatial symmetry of the fundamental bend instability to generate local vortical flows that lead to asymmetric interface fluctuations. The magnitude of interface deformations increases with activity: In the high activity limit, the interface self-folds invaginating passive droplets and generating a foam-like phase, where active fluid is perforated with passive droplets. These results demonstrate how active stresses control the structure, dynamics, and break-up of soft, deformable, and reconfigurable liquid–liquid interfaces.

• Sponsoring Organization: USDOE
• Grant/Contract Number: SC0019733
• OSTI ID: 2480745
• Journal Information: Proceedings of the National Academy of Sciences of the United States of America, Journal Name: Proceedings of the National Academy of Sciences of the United States of America Journal Issue: 51 Vol. 121; ISSN 0027-8424
• Publisher: Proceedings of the National Academy of SciencesCopyright Statement
• Country of Publication: United States
• Language: English