Seminarium Optyczne

A proposition for an entanglement purification scheme based on material qubits and ancillary coherent multiphoton states is made. We consider a typical QED scenario where material qubits implemented by two-level atoms fly sequentially through a cavity and interact resonantly with a single mode of the radiation field. We explore the theoretical possibilities of realizing a high-fidelity two-qubit quantum operation necessary for the purification protocol with the help of a postselective balanced homodyne photodetection. The obtained probabilistic quantum operation can be used as a bilateral operation in the proposed purification scheme. As this protocol requires present-day experimental setups and generates high-fidelity entangled pairs with high repetition rates, it may offer interesting perspectives for applications in quantum information setups