Active assembly and non-reciprocal dynamics of elastic membranes

TL;DR

This paper demonstrates how active fluid-driven fibers can self-assemble into elastic membranes with dynamic, life-like behaviors, bridging the gap between biological and synthetic active matter.

Contribution

It introduces a novel active assembly process that creates hierarchical, dynamic elastic membranes exhibiting non-reciprocal coupling and limit cycles.

Findings

Active fluid flows induce fiber collisions and membrane formation.

The resulting membranes exhibit global limit cycles.

Hierarchical structures emerge from initially structureless suspensions.

Abstract

Equilibrium self-assembly and conventional materials processing techniques fall far short of mimicking dynamic self-actuating processes that are commonplace throughout biology. To bridge the gap between living and synthetic matter, we study adhesive non-thermal fibers immersed in an active fluid. Autonomous chaotic flows power non-equilibrium fiber dynamics, inducing their collisions, generating connections, and weaving a membrane-shaped elastic network. This active assembly generates a hierarchy of shapes, structures, and dynamical processes spanning nanometers to centimeters. Ultimately, it generates an active membrane that exhibits global limit cycles induced by a non-reciprocal coupling between the elastic membrane deformations and the alignment axis of the polar active fluid. Our work merges self-assembly with active matter, demonstrating self-processing materials wherein hierarchical life-like structures and dynamics emerge from an initially structureless suspension.