Cavity QED scheme for realizing the optimal universal quantum cloning of the polarization state of photons

We propose a scheme to realize the optimal universal quantum cloning of the polarization state of the photons in context of a microwave cavity quantum electrodynamics. The scheme is based on the resonant interaction of three-level Λ-type atoms with two cavity modes. The operation requires atoms to fly one by one through the cavity. The interaction time between each of the atoms and the cavity is appropriately controlled by using a velocity selector. The scheme is deterministic, and is feasible by the current experimental technology