Implementation of Ex-OR gate using QCA with NNI logic

Quantum Dot Cellular Automata (QCA) is an intriguing transistor-less technology which can be rendered to switch from the existing CMOS technology. The basic logic state in QCA is determined by the polarity of electrons in a QCA cell rather than voltage level provided by the source. Basically, QCA consists of a majority voter gate and an inverter. Both have their unique representations and are independent of each other. However, when it comes to complex and large circuits, the computation becomes difficult and inefficient. Also, the majority voter gate is not universal in the essence that it doesn't provide an inversion property. In the NAND-NOR-Inverter logic, a single majority gate can be used to form all other logic gates and provides faster speed. In this paper, we focus on the analysis and implementation of Exclusive OR operation through minimum number of QCA cells. We have proposed a new XOR gate realization through NNI logic for which implementation and verification are performed on QCA Designer EDA tool. From the simulation, it was observed that the proposed structure utilizes only 40 cells with area coverage reduced to 0.05 μm
²
in contrast to the existing structure of XOR gate by means of a conventional majority gate.