Topological sound in active-liquid metamaterials

Anton Souslov, Benjamin C. Van Zuiden, Denis Bartolo, Vincenzo Vitelli

Research output: Contribution to journalArticlepeer-review

188 Citations (SciVal)
185 Downloads (Pure)


Liquids composed of self-propelled particles have been experimentally realized using molecular, colloidal or macroscopic constituents. These active liquids can flow spontaneously even in the absence of an external drive. Unlike spontaneous active flow, the propagation of density waves in confined active liquids is not well explored. Here, we exploit a mapping between density waves on top of a chiral flow and electrons in a synthetic gauge field to lay out design principles for artificial structures termed topological active metamaterials. We design metamaterials that break time-reversal symmetry using lattices composed of annular channels filled with a spontaneously flowing active liquid. Such active metamaterials support topologically protected sound modes that propagate unidirectionally, without backscattering, along either sample edges or domain walls and despite overdamped particle dynamics. Our work illustrates how parity-symmetry breaking in metamaterial structure combined with microscopic irreversibility of active matter leads to novel functionalities that cannot be achieved using only passive materials.

Original languageEnglish
Pages (from-to)1091-1094
Number of pages4
JournalNature Physics
Issue number11
Early online date17 Jul 2017
Publication statusPublished - 30 Nov 2017

ASJC Scopus subject areas

  • Physics and Astronomy(all)


Dive into the research topics of 'Topological sound in active-liquid metamaterials'. Together they form a unique fingerprint.

Cite this