Temporal acoustic wave computational metamaterials

Acoustic computational metamaterials have enabled the realization of mathematical operations in the spatial domain. Here, we present and experimentally demonstrate the time domain mathematical operations, such as fractional differentiation and integration and Gaussian filtering, based on a fully reconfigurable acoustic computational metamaterial. We also demonstrate the potential to achieve an integrated computing network in order to realize complicated functionalities by exploiting differentiation, integration, and their series and parallel functions in a simple acoustic metamaterial circuit. For generality and universality, the linearity and the product rule for the wave-based differentiation are also verified as well as the functionality of cascaded differentiators. We expect that acoustic computational metamaterials will enable capabilities in signal acquisition and processing and network computing and drive applications of sound waves.