B andgap of Convertible Metamaterials based on Nonlinearity.

Recently, to enhance the usability of metamaterials, tunable metamaterials have been great attention by combining with many external environments such as temperature, prestressing, electromechanics, electromagnetics, and etc. Among the methods for tunable metamaterials, nonlinear metamaterials have unique potential to achieve bandgap tunability since it is but related on the fe ature of incident wave. Since earlier works for the tunable bandgap based on nonlinearity primarily have focused on the shifting from bandgap of linear metamaterials, the unique bandgap tunability which could be exhibited in only nonlinear metamaterials li ttle has been investigated yet. Here, we proposed nonlinear metamaterials which show unique tunability, convertibility between monoatomic chain and diatomic chain based on nonlinear effective mass. Also we investigated bandgap of the proposed nonlinear met amaterials and carried out numerical simulation for verification