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arXiv · 2002.05567

Nonlinear edge modes in a honeycomb electrical lattice near the Dirac points

Abstract

We examine - both experimentally and numerically - a two-dimensional nonlinear driven electrical lattice with honeycomb structure. Drives are considered over a range of frequencies both outside (below and above) and inside the band of linear modes. We identify a number of discrete breathers both existing in the bulk and also (predominantly) ones arising at the domain boundaries, localized either along the arm-chair or along the zig-zag edges. The types of edge-localized breathers observed and computed emerge in distinct frequency bands near the Dirac-point frequency of the dispersion surface while driving the lattice subharmonically (in a spatially homogeneous manner). These observations/computations can represent a starting point towards the exploration of the interplay of nonlinearity and topology in an experimentally tractable system such as the honeycomb electrical lattice.

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BibTeXRIS

F. Palmero, L. Q. English, J. Cuevas-Maraver, P. G. Kevrekidis. 2020-02-13. Nonlinear edge modes in a honeycomb electrical lattice near the Dirac points. https://doi.org/10.1016/j.physleta.2020.126664

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