Simplified quantum-dot cellular automata implementation of counters

The quantum-dot cellular automata (QCA) circuits are known for their fantastic features such as power consumption, speed and size of circuit. At this paper, a new method of implementing counters as one of the most important blocks of computing systems using QCA is described. This design takes advantage of the binary wires unique characteristics in QCA circuits design. A notable reduction in number of cells and complexity of design is remarkable feature of this design compared to the prior arts. Furthermore, this counter can be simply generalized to any number of bits as the outputs of the counter. Besides, the method of design, layout and simulation results will be presented. Finally a comprehensive analysis on defect characterization of this layout would be given.