Disordered topological mechanical metamaterials

Properties of mechanical metamaterials are largely determined by the structure of the material rather than the composition. Current designs of metamaterials achieve unique mechanical properties such as phononic bandgaps and topological phonon modes by precise control of unit-cell structures, which poses challenges for miniaturization. Recently novel material design techniques have been developed to utilize disordered materials and the slow evolution through their rugged energy landscapes, referred to as directed aging. This kind of design has been used to produce metamaterials with specialized bulk properties. In this talk, we will present our investigation on mechanisms for encoding topological material properties into disordered materials via asymmetrical material preparation. Topological edge floppy modes arise in ordered and disordered materials close to the verge of mechanical instability, and we will show how these modes may be encoded in disordered materials via directed aging, without the need to precisely control the microstructures.