- Letter
Stability-derived bounds on the realizable acoustic properties of active metamaterials
Phys. Rev. Applied 21, L051002 – Published 28 May, 2024
DOI: https://doi.org/10.1103/PhysRevApplied.21.L051002
Abstract
Active acoustic metamaterials consisting of sensor and driver elements that produce a programmed response to impinging acoustic waves have been widely considered an appealing way to overcome the fundamental shortcomings of passive structures. However, research into active metamaterials has been hindered by their potential instability resulting from very complex interactions between cells and the lack of realistic stability models taking these interactions into account. We present a general method for assessing the stability of active metamaterials of arbitrary geometry and number of cells and show that stability imposes previously unknown limitations on the realizable acoustic properties. We validate the theory by accurately predicting the bounds on the realizable effective properties of an experimental metamaterial.
