Mechanical metamaterials for full-band mechanical wave shielding

The manipulation of the interactions between matter and waves is the central theme of metamaterials. The capability of energy shielding in a full frequency band has not yet been achieved. In this paper, a mechanical metamaterial for perfect energy shielding was discovered through a new mechanism by solely circulating energy between a metamaterial and an energy source. Unprecedented energy shielding effects are experimentally demonstrated in low and ultralow vibrational frequency ranges. Along with the widely explored mechanisms, namely, the “energy bypass” and “energy absorption” mechanisms, the “energy shield” mechanism and demonstrated mechanical metamaterial in this paper open a new direction for the design of metamaterials with unprecedented dynamic characteristics in various physical systems at different length scales.