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arXiv · 2408.14699

Active assembly and non-reciprocal dynamics of elastic membranes

John Berezney·Sattvic Ray·Itamar Kolvin·Fridtjof Brauns·Sihan Chen·Mark Bowick·Seth Fraden·Vincenzo Vitelli·Zvonimir Dogic
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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.

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John Berezney, Sattvic Ray, Itamar Kolvin, Fridtjof Brauns, Sihan Chen, Mark Bowick, Seth Fraden, Vincenzo Vitelli, Zvonimir Dogic. 2024-08-26. Active assembly and non-reciprocal dynamics of elastic membranes. https://doi.org/10.1038/s41567-026-03215-5

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