Efficient scheme for implementing an N -qubit Toffoli gate by a single resonant interaction with cavity quantum electrodynamics

A scheme for implementing a three-qubit Toffoli gate with atoms sent through a microwave cavity is proposed by choosing nonidentical coupling constants between the atoms and cavity. The scheme can be generalized to implement an $N$-qubit Toffoli gate and the gating time does not change with an increase of the number of qubits.