Acoustic Metamaterials

Abstract

The field of engineered materials with designed properties is expected to continue to grow in the future, and metamaterials are instrumental in allowing this freedom of design. Metamaterials, particularly acoustic, are still in the stage of infancy. Acoustic metamaterials are being explored theoretically, but there has been little headway on the experimental front. The design, development, and characterization of acoustic metamaterials will offer many opportunities in materials science. In this article, we review the basic physics of different kinds of acoustic periodic structures with special emphasis on locally resonant acoustic metamaterials. We first survey phononic crystals and then discuss localized resonances in intrinsic and inertial resonating structures of acoustic metamaterials. Finally, we present the ongoing efforts in realizing acoustic metamaterials with negative materials properties and discuss the implications of acoustic metamaterials.

Metamaterials: a new frontier of science and technology

“…From eqn (3), it can be readily seen thatk,Ẽ andH form a right-handed triplet of vectors, as a plane wave propagates in normal dielectric materials with e > 0 and m > 0. In contrast, these vectors form a left-handed triplet in materials with e o 0 and m o 0.…”

PT-Symmetric Acoustics

“…Recent advancements in man-made materials ("metamaterials") have resulted in intriguing achievements in acoustic and phononic transport manipulation [1]. These discoveries include dynamic negative density and a bulk modulus [2][3][4][5][6][7][8], subwavelength imaging [9][10][11], acoustic and surface wave cloaking [12][13][14][15], a phononic band gap [16,17], extraordinary acoustic transmission [18,19], Anderson localization [20], and asymmetric transmission [21][22][23][24][25].…”

Nonlinear dynamics of a model of acoustic metamaterials with local resonators

“…An acoustic metamaterial can be regarded as an analogy of electromagnetic metamaterial [8,9]. The acoustic metamaterials can be used to deal with elastic waves instead of electromagnetic waves by a periodic structure with the larger scale than that of the electromagnetic metamaterial.…”