Design of an arithmetic circuit using non-reversible adders in 2 dot 1 electron QCA

Abstract

Quantum-dot cellular automata (QCA) appeared as an alternative nanotechnology which is capable of overcoming the shortfalls of the existing CMOS technologies. This energy efficient technology has a few structural variants such as the 4-dot 2-electron (4:2) QCA variant, the 2-dot 1-electron (2:1) QCA variant. The former one is vastly researched. In this present scope the later one i.e. the 2:1 variant is the one which has a lot to be explored. This article presents design strategy of half adder and full adder using the half adders that have been proposed. Both the designs are reversible by nature. An independent design has been proposed which incorporates only 44 number of cells. All the said designs are implemented using the 2:1 variant of QCA. Further the designs are supposed to give a high quotient of energy efiiciency as it reduces the energy requirement to $$84\%$$ as well as dissipation of energy upto $$90\%$$ . Consequently the proposed independent full adder design is used to develop an arithmetic circuit which contains four such full adder units.