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arXiv · 2307.06729

Landscape of wave focusing and localisation at low frequencies

Bryn Davies·Yiqi Lou
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Abstract

High-contrast scattering problems are special among classical wave systems as they allow for strong wave focusing and localisation at low frequencies. We use an asymptotic framework to develop a landscape theory for high-contrast systems that resonate in a subwavelength regime. Our from-first-principles asymptotic analysis yields a characterisation in terms of the generalised capacitance matrix, giving a discrete approximation of the three-dimensional scattering problem. We develop landscape theory for the generalised capacitance matrix and use it to predict the positions of three-dimensional wave focusing and localisation in random and non-periodic systems of subwavelength resonators.

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Bryn Davies, Yiqi Lou. 2023-07-13. Landscape of wave focusing and localisation at low frequencies. https://arxiv.org/abs/2307.06729

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