On the basis of the principle of nonlinear optics

the conjugated metallic periodic structure with nonlinear optic material can realize all-optical switches.It is found from the numeric simulation of the electromagnetic field near nano-structure that its surface plasmons demonstrate distinct enhancement of the local field

which greatly increases the third-order nonlinear effect of the nonlinear material and makes the all-optical control still more dominant

thus reducing the threshold power of the switches and realizing super-fast response speed.It is expected to be widely applied in the future all-optical communication networks.