Design of combinational logic circuits for low power reversible logic circuits in quantum cellular automata

The circuits like Logic gates, Adders, Multipliers are the basic building block of the digital circuits. These combinational circuits can be designed by using the concepts of the reversible logic. The reversible logic is either a physically reversible or logically reversible. In this paper the combinational circuits are logically reversible. One of the applications of the reversible logic is Quantum Cellular Automata (QCA). QCA has attracted feature of extremely small feature size (at the molecular or even atomic scale) and its ultra-low power consumption, making it one candidate for replacing CMOS technology. Thus the design and realization of the Basic Logic gates and Combinational circuits like ripple carry adder, serial adder, multiplexer are done by using the concept of Quantum Cellular Automata. Also, the area and cost of the QCA system is reduced with the help of Coplanar architecture arrangement of cells. The paper is organized as follows; the section one gives the overall introduction about QCA, Clocking of QCA and Wires in QCA. Section two gives information about the basic logic gates. In Section three, design and Simulation of Combinational circuits like half adder, full adder, ripple carry adders and multipliers are discussed. At last the Comparison of Quantum cost of the above designs due to Coplanar architecture was elaborated.