Work

Emergence of Order in Chemically Active Droplets: Temporal Dynamics and Collective Behavior

Year: 2025

Type: article

Abstract: Collective behaviors such as swarming, chemical signaling, and clustering are fundamental to biological microorganisms, enabling hierarchical colony formation, coordinated motion, and enhanced nutrient accessibility─crucial for their survival. Over the past few decades, active droplets have emerged as valuable synthetic analogues, effectively replicating key biological attributes and serving as ideal platforms for investigating collective phenomena. This research explores the collective behavior of 4-cyano-4′-pentylbiphenyl (5CB) oil droplets across varying Péclet ( Pe ) numbers. At high Pe, droplets exhibit a pusher mode of propulsion and form dynamic chain-like patterns. Decreasing Pe enhances repulsive interactions among droplets, resulting in the inhibition of clustering. These repulsive interactions, mediated by chemical fields, lead to the emergence of an ordered structure at low Pe . Furthermore, we also illustrate how active droplets of larger size efficiently navigate within such a soft structured environment. These findings significantly contribute to our comprehension of self-organized phenomena in active matter systems.

Source: Langmuir

DOI: 10.1021/acs.langmuir.5c03948

Authors: Sobiya Ashraf, Pawan Kumar, Prateek Dwivedi, Frédéric Blanc, Dipin Pillai, Rahul Mangal

Institutions: Université Côte d'Azur, Institut de Physique de Nice, Communauté d'universités et d'établissements Université Côte d'Azur

Language: English

Topic: Micro and Nano Robotics

Subfield: Condensed Matter Physics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: green

Funders: Department of Science and Technology, Ministry of Science and Technology, India, Science and Engineering Research Board

Awards: G2515937971, G3933536469, G798244741