 Nonlinear metamaterial

Nonlinear metamaterials are artificial materials engineered to have properties that deviate from those of natural materials, particularly in the way they respond to electromagnetic waves. What distinguishes nonlinear metamaterials from linear metamaterials is their response to the intensity of electromagnetic fields — in nonlinear metamaterials, the response (such as permittivity or permeability) can change with the strength of the applied field. This nonlinearity can give rise to various novel optical and electronic effects not typically observed in linear materials.