Demonstration of nonlinear magnetoelectric coupling in metamaterials

We demonstrate nonlinear magnetoelectric coupling in a varactor-loaded metamaterial at microwave frequencies. The nonlinear magnetoelectric coupling takes the form of second-harmonic generation in which incident magnetic fields at frequency ω drive an electric polarization at frequency 2ω. The magnitudes and phases of the generated signals from two nonlinear metamaterials are measured, verifying the dominant nonlinear process in each sample. We expect the metamaterial design employed in this letter to form the prototype for future investigations into nonlinear magnetoelectric coupling. © 2012 American Institute of Physics.