Implementing quantum Fourier transform using three qubits

Abstract

Based on the circulant symmetry we give a proposal about the physical realization of the quantum Fourier transform gate. This symmetry allows us to construct a set of eigenvectors independently on the magnitude of physical parameters characterizing our system and as a result, the entanglement will be protected. The implementation of the present gate requires an adiabatic transition from each spin product state to Fourier modes. The fidelity was numerically calculated and the results show important values. Finally, we describe that we can accelerate the gate by using the counter-driving field.