Artificial Kerr-type medium using metamaterials.

We investigated an artificial Kerr-medium realized by actuated THz metamaterials. Instead of directly applying E-field inside the medium, we use micromechanical systems actuated by voltage to tune the phase shift. We established that the combined system can have a relationship between the phase shift and the voltage similar to a Kerr cell. A metamaterial Kerr-cell is designed to modulate the transmission phase difference by 0.99 degrees/V-2 which is much stronger than natural Kerr crystals. It is attributed to the mechanical tunability of metamaterials with high indices in two orthogonal directions. A Lorentzian model is used in explaining the artificial Kerr cell. (C) 2012 Optical Society of America