A novel universal (FNZ) gate in quantum dot cellular automata (QCA)

As transistor geometries are reduced, quantum effects begin to dominate device performance. At some point, transistors cease to have the properties that make them useful computational components. New computing elements must be developed in order to keep pace with Moore´s Law. Quantum dot cellular automata (QCA) represent an alternative paradigm to transistor-based logic. It has attractive features such as faster speed, smaller size and low power consumption than transistor based technology. By taking the advantages of QCA, we are able to design interesting computational architectures. QCA architectures have been designed by employing either the inverter and the majority gate or universal gates such as And-Or-Inverter (AOI) and Nand-Nor-Inverter (NNI). A new universal QCA logic gate called as FNZ gate is introduced in this paper which enjoys superior performance vis-à-vis the already introduced universal gates. The implementation of various logic functions using the proposed FNZ Gate is also demonstrated. The functionality of the FNZ Gate designs is verified by QCA Designer tool where a detailed comparison with the previously reported designs confirms the reliable performance of the proposed designs.