Cascading Application of all Optical Universal NAND Gate for Implementation of Basic Logic Gates

All optical logic gates has been a prime area of research in the past. Several notable attempts have been made and many designs have been proposed. One of the important aspects in the use of these logic gates is the feasibility of their cascaded operation which has been overlooked so far. In order to develop large scale integrated photonic circuits it is very much necessary to check whether the logic gates can operate satisfactorily when connected in cascade. This paper focuses on discussing the cascade connection applications of all optical NAND gate developed using microring resonators. Development of other optical logic gates using the universal NAND gate is proposed. Inputs applied have a fixed power of 0.25 W and the NAND gate used to develop other logic gates has output power level around 0.20 W and 0.05 W for high and low logic respectively. Logic operations such as AND, OR, XOR, XNOR are successfully demonstrated. The results obtained from cascade connection indicate the possibility of utilizing the NAND gate for construction of several combinational circuits which can be a very important step to develop large scale photonic integrated circuits.