Experimental characterization of rigid-scatterer hyperuniform distributions for audible acoustics

Abstract

[EN] The wave transport properties of two-dimensional stealthy hyperuniform distributions of rigid scatterers embedded in a waveguide are experimentally characterized for scalar waves in airborne audible acoustics. The nonresonant nature of the scatterers allows us to directly link these properties to the geometric distribution of points through the structure factor. The transport properties are analyzed as a function of the stealthiness x of their hyperuniform point pattern and compared to those of a disordered material in the diffusive regime, which are characterized by the Ohm's law through both the classical mean free path and the corrected mean free path by the collective approximation considering the effects of correlation. Different scattering regimes are theoretically and numerically identified showing transparent regions, isotropic band gaps, and anisotropic scattering depending on x. The robustness of these scattering regimes to losses, which are unavoidable in audible acoustics is experimentally unveiled.