Design and Simulation of Optical Logic Gates Based on (MIM) Plasmonic Waveguides and slot cavity resonator for Optical Communications

Abstract

In the field of optics the tinier devices are the better; therefore, the diffraction limit of light seems like an essential limitation in the way of that field. In return, new methods have appeared to resolve this issue. One of these methods is the plasmonic technology which allows light pressure into nanostructures. The current study proposes all-optical logic gates based on metal insulator metal structures (mim) waveguide. This waveguide has an important characteristic which is restricting the applied light strongly far from the diffraction limit. The proposed structure is small compared to the applied wavelength. The optical plasmonic gates proposed are (OR, NOR, AND, NAND, NOT). The comsol multiphysics 5.5 software was used for simulation by the 2-D FDTD method. Hence, these five gates will be obtained by optical interference between the propagating signals through the input ports and the control ports, whose positions can be altered according to the gate needed. The implementation and simulation of the proposed gates were all in the same structure, with the same dimensions, the same wavelength and the same transmission threshold, with applicable wavelength of (1550 nm). The performance of the proposed plasmonic gates was tested by two criteria; the optical transmission ratio and the contrast ratio, which is the ratio between the ON and OFF states of the proposed gate..