  The physical limitations of CMOS technology triggered several research for
finding an alternative technology. QCA is one of the emerging nanotechnologies
which is gaining attention as a substitute of CMOS. The main potential of QCA
is its ultra low power consumption, less area overhead, and high speed.
Majority and inverter gates are the basic gates in QCA,which together works as
a universal logic gate to implement any QCA circuit. This paper proposes an
efficient methodology for optimal QCA circuit synthesis of arbitrary
multi-output boolean functions. A multi-objective genetic algorithm based
approach is used to reduce worst case delay and gate count of a QCA circuit.
Different importance is given to worst case delay, no. of majority and no. of
inverter gates. Several efficient techniques are used in order to achieve the
optimal result and reduce the computational complexity furthermore additional
methodologies are used to eliminate redundancies from the final solution.
Comparison of the obtained results with the existing best techniques indicates,
the proposed technique outperforms in terms of worst case delay and gate count.
