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arXiv · 1512.01545

Parabolic Metamaterials and Dirac Bridges

D. J. Colquitt·N. V. Movchan·A. B. Movchan
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Abstract

A new class of multi-scale structures, referred to as `parabolic metamaterials' is introduced and studied in this paper. For an elastic two-dimensional triangular lattice, we identify dynamic regimes, which corresponds to so-called `Dirac Bridges' on the dispersion surfaces. Such regimes lead to a highly localised and focussed unidirectional beam when the lattice is excited. We also show that the flexural rigidities of elastic ligaments are essential in establishing the `parabolic metamaterial' regimes.

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D. J. Colquitt, N. V. Movchan, A. B. Movchan. 2015-12-01. Parabolic Metamaterials and Dirac Bridges. https://doi.org/10.1016/j.jmps.2016.05.006

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