Asymmetric fluctuations and self-folding of active interfaces

• 成果类型: Article
• 署名作者: Zhao, Liang; Gulati, Paarth; Caballero, Fernando; Kolvin, Itamar; Adkins, Raymond; Marchetti, M. Cristina; Dogic, Zvonimir
• 署名单位: University of California System; University of California Santa Barbara; Brandeis University; University System of Georgia; Georgia Institute of Technology; Yale University; University of California System; University of California Santa Barbara
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-12522
• DOI: 10.1073/pnas.2410345121
• 发表日期: 2024-12-10
• 关键词: dynamics; tension

摘要

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.