Reliable and Tunable Elastic Interface States in Soft Metamaterials

Abstract

Tunable elastic interface states in soft materials have been successfully observed in experiments recently, which provides great application potentials in dynamic vibration energy‐harvesting devices or mechanical control of soft robotics. However, the generation of the proposed tunable elastic interfacial states relies on two differently deformed soft periodic phononic crystals, and complicated mechanical loadings and external installations are inevitable, which are indeed difficult to generate and manipulate. Herein, the dynamically adjustable elastic localized states are implemented in a more reliable and convenient way, which is readily modulated simply through compressing or stretching a mirror‐symmetric metamaterial composite simultaneously. The primitive cell of the soft periodic structures is inspired by the symmetry‐broken hexagonal boron nitride structure. Repeatable and reversible frequency shift and switch on–off characteristics of the interface states are observed during the dynamical regulation process, which is used in the dynamic elastic filter or divider devices. The feasibility of utilizing mirror operation to produce the interface states is clearly demonstrated, which effectively reduces the geometry and configuration design during the manufacturing process. The mirror method is also generalized to other periodic photonic and phononic crystals for the generation of additional multiple tunable interface states.