Physics

Acoustic attenuation

Optics

Metamaterial

Vibration

Sound (geography)

Acoustic metamaterials

Acoustics

Attenuation

Scattering

Materials science

Acoustic wave

Stiffness

Broadband

Thermodynamics

Physical Review Applied

Phononic crystals and acoustic metamaterials are architected lattices designed to control the propagation of acoustic or elastic waves. In these materials, the dispersion properties and the energy transfer are controlled by selecting the lattices' geometry and their constitutive material properties. Most designs, however, only affect one mode of energy propagation, transmitted either as acoustic, airborne sound or as elastic, structural vibrations. Here, we present a design methodology to attenuate both acoustic and elastic waves simultaneously in all polarizations. We experimentally realize the first three-dimensional, load bearing, architected lattice, composed of a single-material, that responds in a broadband frequency range in all directions.

Architected Lattices for Simultaneous Broadband Attenuation of Airborne Sound and Mechanical Vibrations in All Directions