A novel nondeterministic scheme for a nondestructive two-qubit controlled phase gate with linear optics

A linear optical scheme for realizing the nondeterministic two-qubit quantum controlled phase gate is presented. The proposed setup involves a pair of product states, polarizing beam splitters, phase shifters and photon number resolving detectors. The omission of entangled ancilla input and additional single-qubit operations significantly reduces the complexity of this gate. This can be well implemented in experiment.