Stealth and equiluminous materials for scattering cancellation and wave diffusion

Abstract

We report a procedure to design two-dimensional acoustic structures with prescribed scattering properties. The structures are designed from targeted properties in the reciprocal space so that their structure factors, i.e. their scattering patterns under the Born approximation, exactly follow the desired scattering properties for a set of wavelengths. The structures are made of a distribution of rigid circular cross-sectional cylinders embedded in air. We demonstrate the efficiency of the procedure by designing two-dimensional stealth acoustic materials with broadband back-scattering suppression independent of the angle of incidence and equiluminous acoustic materials exhibiting broadband scattering of equal intensity also independent of the angle of incidence. The scattering intensities are described in terms of both single and multiple scattering formalisms, showing excellent agreement with each other, thus validating the scattering properties of each material.

Keywords:

• Acoustic scattering cancellation
• acoustic wave diffusion
• stealth materials
• hyperuniform materials

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work has been funded by the project Conseil Régional des Pays de la Loire HYPERMETA under the program Étoiles Montantes of the Région Pays de la Loire, by the project Agence Nationale de la Recherche ANR-RGC METARoom [grant number (ANR-18-CE08-0021)] and by the project PID2020-112759GB-I00 of the Ministerio de Ciencia e Innovación.