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..

The motivation of this study springs from the need of exploiting the advantages of high data rate and increased mobility of the transmitted signal in the Next Generation Passive Optical Network stage 2 (NG-PON2) incorporated into Radio over Fiber (RoF) system. Nonetheless, such system is prone to degradation due to the nonlinear effects, namely, the non-linear impairments. Accordingly, this study suggests a design for a full-duplex NG-PON2-RoF system and it investigates the impact of the nonlinear effects on the performance of system, such as; Self-Phased Modulation (SPM), Cross-Phase Modulation (XPM), and Four-Wave Mixing (FWM). However, these effects would result in a significant data loss in Time and Wavelength Division Multiplexing-Passive Optical Network (TWDM-PON). To achieve the intended purpose of this investigation, both the performance of the suggested system and the nonlinear effects of SPM, XPM, and FWM are measured with reference to the qualitative parameters, such as; Bit Error Rate (BER), Q-Factor, Power link Budget, and the Eye-diagram. The results show that the system performs efficiently; however, in the presence of the nonlinear effects, the performance of the systems degrades significantly affecting the signal quality. It is worth noting that the FWM effect yields the most negative impact followed by the XPM, and the SPM effect yields the least significant impact on the system. Also, the system yields the capacity of transmitting range of 20-100 Km, and it results in data rate of 40-80 Gbps. The proposed system is simulated using the software Optisystem 15.