Feynman gate based design of n-bit reversible inverter and its implementation on quantum-dot cellular automata

Abstract

This paper proposed the design of n-bit controllable inverter using reversible logic and implementation based on QCA. The proposed inverter is designed by cascading Feynman gates. Conventional technology based implementation cost, i.e., quantum cost is compared with QCA based implementation cost. This comparative study shows the cost effective implementation in QCA. Besides n-bit controllable inverter, the design of 2-bit double controllable inverter is also proposed using Feynman gate and is implemented using QCA. The evaluation of those designs are performed using parameters like the number of QCA cells, majority voters, inverters, areas, clocking zones and circuit cost. The simulation output is evaluated based on theoretical values which established that all the circuits are functioning accurately. The proposed CNOT gate is superior in cell count and device area. The designs have less area-delay cost than conventional design. The stuck-at-fault analysis of those proposed inverters is performed and to achieve 100% fault coverage of proposed circuits, a set of test vector has been proposed. The proposed circuits can be used as a basic component for more powerful low energy dissipated nano-scale reversible adder/subtractor circuit.