ABSTRACT

Quantum cellular automata (QCA) is a new technology in the nanometer scale and has been considered as one of the alternative to CMOS technology. QCA have a large potential in the development of circuits with high space density and low heat dissipation and allow the development of faster computers with lower power consumption. This paper discusses the design and construction of simple two bit arithmetic logic unit , four bit shifter and carry save in multiplier circuits. The advantage of this type of ALU is to construct functional unit all around the input lines and thereby reducing circuit complexity. Four bit shifter are constructed using serial AND and OR QCA circuits. QCA multiplier designed and constructed here has advantage of carry save in by delaying one clock cycle and no of bits can also be increased by adding the full adder stages. These circuits are the building block of nanoprocessors and provide us to understand the nanodevices of the future.