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Interfacial waveforms in chiral lattices with gyroscopic spinners.

ABSTRACT: We demonstrate a new method of achieving topologically protected states in an elastic hexagonal system of trusses by attaching gyroscopic spinners, which bring chirality to the system. Dispersive features of this medium are investigated in detail, and it is shown that one can manipulate the locations of stop-bands and Dirac points by tuning the parameters of the spinners. We show that, in the proximity of such points, uni-directional interfacial waveforms can be created in an inhomogeneous lattice and the direction of such waveforms can be controlled. The effect of inserting additional soft internal links into the system, which is thus transformed into a heterogeneous triangular lattice, is also investigated, as the hexagonal lattice represents the limit case of the heterogeneous triangular lattice with soft links. This work introduces a new perspective in the design of periodic media possessing non-trivial topological features.

SUBMITTER: Garau M

PROVIDER: S-EPMC6083240 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature

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Interfacial waveforms in chiral lattices with gyroscopic spinners.

Garau M M Carta G G Nieves M J MJ Jones I S IS Movchan N V NV Movchan A B AB

Proceedings. Mathematical, physical, and engineering sciences 20180725 2215

We demonstrate a new method of achieving topologically protected states in an elastic hexagonal system of trusses by attaching gyroscopic spinners, which bring chirality to the system. Dispersive features of this medium are investigated in detail, and it is shown that one can manipulate the locations of stop-bands and Dirac points by tuning the parameters of the spinners. We show that, in the proximity of such points, uni-directional interfacial waveforms can be created in an inhomogeneous latti ...[more]

PMID: 30100810

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