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arXiv · 0811.0497

Tripartite entanglement transfer from flying modes to localized qubits

Federico Casagrande·Alfredo Lulli·Matteo G. A. Paris
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Abstract

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 qubit-like and Gaussian entangled states in terms of field parameters, atom-cavity interaction time, cavity mirror losses, and atomic preparation. For qubit-like states we found 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 found a range of field parameters 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 details.

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Federico Casagrande, Alfredo Lulli, Matteo G. A. Paris. 2008-11-04. Tripartite entanglement transfer from flying modes to localized qubits. https://doi.org/10.1103/physreva.79.022307

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