Dispersion suppression of guided elastic waves by anisotropic metamaterial

This investigation presents a method to engineer a metamaterial exhibiting the desired anisotropic wave behavior with the specific applications toward the dispersion suppression of elastic guided waves. In the proposed approach, effective anisotropic properties required for dispersion suppression were first determined. Then the slowness curves for the metamaterial were used to find the specific unit cell configuration through inverse design. When the metamateral layers were attached to the homogeneous waveguide, the target guided mode was shown to exhibit little dispersion. Detailed engineering procedures were given, and the direct numerical simulations were performed to confirm the effectiveness of the proposed approach.