Coarsening of liquid droplets in an active fluid

Coarsening, the growth of larger structures at the expense of smaller ones, is a fundamental process in multiphase systems. Duclos and Rogers mixed phase-separating DNA nanostars in a reconstituted active fluid. This effort aligns with the goal of IRG2: designing active composite materials by dispersing active building blocks within diverse passive soft materials. Here, the passive condensates are advected by the active flows and coarsen over time following a power law. Baskaran performed simulations demonstrating that the coarsening exponents are determined by the statistics of binary droplet collisions, which in turn depend on their motility. Duclos demonstrated that droplets' motility is independent of their size when immersed in an active fluid. These results are generalizable to volume-conserving coarsening in various flow environments and may offer insights into other natural processes, such as blood clot formation