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Topological mechanics of gyroscopic metamaterials.

ABSTRACT: Topological mechanical metamaterials are artificial structures whose unusual properties are protected very much like their electronic and optical counterparts. Here, we present an experimental and theoretical study of an active metamaterial--composed of coupled gyroscopes on a lattice--that breaks time-reversal symmetry. The vibrational spectrum displays a sonic gap populated by topologically protected edge modes that propagate in only one direction and are unaffected by disorder. We present a mathematical model that explains how the edge mode chirality can be switched via controlled distortions of the underlying lattice. This effect allows the direction of the edge current to be determined on demand. We demonstrate this functionality in experiment and envision applications of these edge modes to the design of one-way acoustic waveguides.

SUBMITTER: Nash LM

PROVIDER: S-EPMC4664354 | biostudies-literature | 2015 Nov

REPOSITORIES: biostudies-literature

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Topological mechanics of gyroscopic metamaterials.

Nash Lisa M LM Kleckner Dustin D Read Alismari A Vitelli Vincenzo V Turner Ari M AM Irvine William T M WT

Proceedings of the National Academy of Sciences of the United States of America 20151111 47

Topological mechanical metamaterials are artificial structures whose unusual properties are protected very much like their electronic and optical counterparts. Here, we present an experimental and theoretical study of an active metamaterial--composed of coupled gyroscopes on a lattice--that breaks time-reversal symmetry. The vibrational spectrum displays a sonic gap populated by topologically protected edge modes that propagate in only one direction and are unaffected by disorder. We present a m ...[more]

PMID: 26561580

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