Tripartite entanglement transfer from flying modes to localized qubits
Federico Casagrande, ALFREDO LULLI, Matteo G. A. Paris · Physical Review A · 2009
We investigate the process of entanglement transfer from a three-mode quantized field to a system of three spatially separated qubits, each one made of a two-level atom resonantly coupled to a cavity mode. The optimal conditions for entanglement transfer, evaluated by atomic tripartite negativity, are derived for radiation prepared in qubitlike and Gaussian entangled states in terms of field parameters, atom-cavity interaction time, cavity mirror losses, and atomic preparation. For qubitlike states we find that for negligible cavity losses some states may completely transfer their entanglement to the atoms and/or be exactly mapped to the atomic state, whereas for Gaussian states we find a range of field parameters needed to obtain a large entanglement transfer. The purity of the three-qubit states and the entanglement of two-qubit subsystems are also discussed in some detail.