Acoustic Metamaterials

At the INTERACT Lab we use specially engineered materials (“meta-” in metamaterials means “beyond”) to shape sound. They are based on 3D-printed, LEGO-like bricks that can be assembled into 3D structures, transforming the sound that passes through them. We have shown that just 16 types are sufficient to get any desired shape of sound with a fidelity beyond detection and invented an algorithm that allows to create assembling instructions for a desired sound shape.

Manipulating sound may seem far fetched, but multi-speaker arrays are used to this aim in haptics, medical diagnostic and therapy, crack detection, high-end Hi-Fi systems. When the number of channels increases, though, the price of these devices increases very quickly. We are now working on metamaterial-based devices that are more cost-effective and user-controllable: they will give us directional acoustic messages that can be touched in mid air.


Gianluca Memoli, Mihai Caleap, Michihiro Asakawa, Deepak R Sahoo, Bruce W Drinkwater, Sriram Subramanian, Metamaterial bricks and quantization of meta-surfaces, Nat Comms 8, 14608 (2017) (paper)