Cavity-quantum-electrodynamics entangled photon source based on two truncated Rabi oscillations

We discuss a cavity-QED scheme to deterministically generate entangled photons pairs by using a three-level atom successively coupled to two single longitudinal mode high-Q cavities presenting polarization degeneracy. The first cavity is prepared in a well-defined Fock state with two photons with opposite circular polarizations while the second cavity remains in the vacuum state. Half of a resonant Rabi oscillation in each cavity transfers one photon from the first to the second cavity, leaving the photons entangled in their polarization degree of freedom. The feasibility of this implementation and some practical considerations are discussed for both microwave and optical regimes. In particular, Monte Carlo wave-function simulations have been performed with state-of-the-art parameter values to evaluate the success probability of the cavity-QED source in producing entangled photon pairs as well as its entanglement capability.