Figure 2
From: Electronic Metamaterials with Tunable Second-order Optical Nonlinearities

(a) The log-log plot of measured SHG signal versus pump power for a single layer of Al (red triangles), Ni (blue squares) film and MSM metamaterial (black circles) grown on silica substrates for a fixed pump-beam incident angle of 45°. (b) The generated p-polarized and (c) s-polarized SHG intensity versus polarization angle for a 100 mW pump.