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Robust temporal pumping in a magneto-mechanical topological insulator.

ABSTRACT: The transport of energy through 1-dimensional (1D) waveguiding channels can be affected by sub-wavelength disorder, resulting in undesirable localization and backscattering phenomena. However, quantized disorder-resilient transport is observable in the edge currents of 2-dimensional (2D) topological band insulators with broken time-reversal symmetry. Topological pumps are able to reduce this higher-dimensional topological insulator phenomena to lower dimensionality by utilizing a pumping parameter (either space or time) as an artificial dimension. Here we demonstrate a temporal topological pump that produces on-demand, robust transport of mechanical energy using a 1D magneto-mechanical metamaterial. We experimentally demonstrate that the system is uniquely resilient to defects occurring in both space and time. Our findings open a path towards exploration of higher-dimensional topological physics with time as a synthetic dimension.

SUBMITTER: Grinberg IH

PROVIDER: S-EPMC7033202 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

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Robust temporal pumping in a magneto-mechanical topological insulator.

Grinberg Inbar Hotzen IH Lin Mao M Harris Cameron C Benalcazar Wladimir A WA Peterson Christopher W CW Hughes Taylor L TL Bahl Gaurav G

Nature communications 20200220 1

The transport of energy through 1-dimensional (1D) waveguiding channels can be affected by sub-wavelength disorder, resulting in undesirable localization and backscattering phenomena. However, quantized disorder-resilient transport is observable in the edge currents of 2-dimensional (2D) topological band insulators with broken time-reversal symmetry. Topological pumps are able to reduce this higher-dimensional topological insulator phenomena to lower dimensionality by utilizing a pumping paramet ...[more]

PMID: 32080188

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