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arXiv · 2409.04097

Wave packets propagation in the subwavelength regime near the Dirac point

Habib Ammari·Xin Fu·Wenjia Jing
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Abstract

In [Ammari et al., SIAM J Math Anal., 52 (2020), pp. 5441--5466], the first author with collaborators proved the existence of Dirac dispersion cones at subwavelength scales in bubbly honeycomb phononic crystals. In this paper, we study the time-evolution of wave packets that are spectrally concentrated near such conical points. We prove that the wave packets dynamics is governed by a time-dependent effective Dirac system, which still depends, but in a simple way, on the subwavelength scale.

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Habib Ammari, Xin Fu, Wenjia Jing. 2024-09-06. Wave packets propagation in the subwavelength regime near the Dirac point. https://arxiv.org/abs/2409.04097

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