Inverse design of reconfigurable metabeams: Harnessing multi-wave coupling for tailored dispersion

The roton-like dispersion has recently been realized in elastic metamaterials through the introduction of the nonlocal effect, which is facilitated by beyond-nearest-neighbor interactions. Here, we propose an innovative but simple reconfigurable structure composed of a rectangular beam integrated with an array of oblique quadrangular prisms. This design leverages structural symmetry to control wave coupling, enabling precise tuning of dispersion characteristics and the creation of extremum points (EPs). By manipulating the symmetry and coupling mechanisms, we can selectively design structures that promote the interaction of specific wave types , achieving targeted dispersion patterns. Through this inverse design approach, we can control the number and location of EPs, effectively customizing the dispersion profile to meet desired specifications, including the realization of maxon-like and roton-like dispersions. Comprehensive simulations and experimental validation have confirmed the feasibility of achieving high-precision control over the dispersion characteristics. This groundbreaking approach paves the way for advanced wave manipulation in elastic metamaterials .