Piezoelectric metamaterial with digitally controlled nonlinear shunt circuit for broadband wave attenuation

This Letter reports a nonlinear piezoelectric metamaterial with pure digital inductance shunt circuits for adjustable broadband wave attenuation. The proposed nonlinear piezoelectric metamaterial is comprised of arrayed piezoelectric unit-cells with individually connected digital nonlinear inductive shunt circuits. Taking advantage of the programmed nonlinear behavior of the shunt circuits, we can expand the frequency region of wave attenuation at an arbitrary frequency. This broadband wave attenuation mechanism is facilitated by modifying the poles, zeros, and nonlinearity in the control algorithm, whereas the mechanical and electrical configurations are not altered. Our experimental analysis confirmed the adjustability and broadband features of the proposed system. The results demonstrated 3.84 times enlargement of the bandwidth under negative nonlinear coefficient K of −3 × 10−12. This piezoelectric metamaterial shows promising potential for active control in broadband wave attenuation.