New All-optical Switch Based on the Local Nonlinear Plasmonic Mach-Zehnder Interferometer Waveguides

In this paper, we proposed a new all-optical switch based on the local nonlinear metal-insulator-metal (MIM) plasmonic Mach-Zehnder (MZ) interferometer waveguides. The proposed structure is composed of the local Kerr type nonlinear MIM plasmonic MZ interferometer waveguide and the straight MIM plasmonic control waveguide. In recent year, the surface plasmon has attracted much attention due to the potential of application. Surface plasmon polariton (SPP) is an electromagnetic excitation at the interface of dielectrics and metals, which can be used to control light in subwavelength. The local Kerr type nonlinear MIM plasmonic MZ interferometer waveguide is used in this switching structure for its large third-order nonlinear susceptibility and ultrafast response properties. Some important optical properties of the switching structure have been studied numerically by the finite-difference time-domain method (FDTD), including the transmission characteristics and the switching effect. The proposed new all-optical switching structure shows great advantages of the ultracompact device size and the ultrafast switching effect. By properly fixing the input signal power and changing the control power, the output signal beam will show the switching effect. In this structure we can found that the proposed all-optical switch exhibits an excellent switching effect. It would be a potential key component in the application of the ultra-high-speed data processing system.