Modulation of Splitting Beam Angle with Metal–Nonlinear Optical Material–Metal (M-NL-M) Array Structure

We demonstrate active manipulating plasmonic signals with metal-nonlinear optical material–metal (M-NL-M) arrays consisting of slits with variant widths. The parameters of the M-NL-M array structure are derived by theoretical analysis of dispersion relationship. The splitting angle can be modulated by the incident light intensity, and verified by a nonlinear two-dimensional finite difference time domain method. The physical principle of this phenomenon is analysed from the phase of surface plasmon polaritons and Fabry–Pérot (F-P) resonance in slits