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arXiv · 2111.12001

Metamaterial shields for inner protection and outer tuning through a relaxed micromorphic approach

Gianluca Rizzi·Patrizio Neff·Angela Madeo
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Abstract

In this paper, a coherent boundary value problem to model metamaterials' behavior based on the relaxed micromorphic model is established. This boundary value problem includes well-posed boundary conditions, thus disclosing the possibility of exploring the scattering patterns of finite-size metamaterials' specimens. Thanks to the simplified model's structure (few frequency- and angle-independent parameters), we are able to unveil the scattering metamaterial's response for a wide range of frequencies and angles of propagation of the incident wave. These results are an important stepping stone towards the conception of more complex large-scale meta-structures that can control elastic waves and recover energy.

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Gianluca Rizzi, Patrizio Neff, Angela Madeo. 2021-11-23. Metamaterial shields for inner protection and outer tuning through a relaxed micromorphic approach. https://doi.org/10.1098/rsta.2021.0400

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