  While advances in quantum hardware occur in modest steps, simulators running
on classical computers provide a valuable test bed for the construction of
quantum algorithms. Given a unitary matrix that performs certain operation,
obtaining the equivalent quantum circuit, even if as an approximation of the
input unitary, is a non-trivial task and can be modeled as a search problem.
This work presents an evolutionary search algorithm based on the island model
concept, for the decomposition of unitary matrices in their equivalent circuit.
Three problems are explored: the coin for the quantum walker, the Toffoli gate
and the Fredkin gate. The algorithm proposed proved to be efficient in
decomposition of quantum circuits, and as a generic approach, it is limited
only by the available computational power.
