Simulation of all-optical NOT/OR/AND/NAND/NOR/XNOR/XOR logic gates using a single structure high contrast index nonlinear multimode interference coupler

An compact 3 × 3 polydiacetylene crystalian multimode interference (MMI) coupler simulated using the nonlinear modal propagation method (NMPA) is proposed as a conventional-single structure to fulfill the functionality of all kind of logic gates based on OOK format. This novel approach has potential application in all-optical logic gates for Boolean logic signal processing devices. We consider three categories of input arrangements to investigate six logic output situations such A side-input control of the gate operations with an opposite-side output is demonstrated to produce all the binary functions. Therefore, logic gates operations are optimized via the output width, where the contrast ratio between the ON and OFF states determines the efficiency of the all-optical gates, such as, contrast ratios lying from 22 dB to 12 dB on the optimized output width.