Robust temporal pumping in a magneto-mechanical topological insulator

Inbar Hotzen Grinberg,Wladimir A Benalcazar,Gaurav Bahl,Cameron Harris,Christopher W Peterson,Mao Lin,Taylor L Hughes

doi:10.1038/s41467-020-14804-0

Inbar Hotzen Grinberg, Wladimir A Benalcazar + Show 5 more

Open Access

https://doi.org/10.1038/s41467-020-14804-0

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Journal: Nature Communications	Publication Date: Feb 20, 2020
Citations: 72	License type: open-access

Affiliation: University of Illinois Urbana-Champaign

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.

Highlights

The transport of energy through 1-dimensional (1D) waveguiding channels can be affected by sub-wavelength disorder, resulting in undesirable localization and backscattering phenomena
It was shown that periodic, adiabatic, spatiotemporal modulations of a 1D periodic potential can produce quantized particle transport[12] where the number of particles pumped in one cycle is equal to the Chern number defined on the (1 + 1)-dimensional Brillouin zone spanned by momentum and time[13]
We demonstrate a temporal topological pump using a 1D metamaterial composed of magnetically-coupled mechanical resonators

Summary

Introduction

The transport of energy through 1-dimensional (1D) waveguiding channels can be affected by sub-wavelength disorder, resulting in undesirable localization and backscattering phenomena. Without loss of generality let the pumping phase φ = 0 or 2π represent the array in the topologically non-trivial phase, with two edge modes within the bandgap that are degenerate in frequency and positioned on opposite ends of the chain (see Supplementary Note 8).

Results

Conclusion