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Entanglement and the SU(2) phase states in atomic systems

M. Ali Can·Alexander A. Klyachko·Alexander S. Shumovsky
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Abstract

We show that a system of 2n identical two-level atoms interacting with n cavity photons manifests entanglement and that the set of entangled states coincides with the so-called SU(2) phase states. In particular, violation of classical realism in terms of the GHZ and GHSH conditions is proved. We discuss a new property of entanglement expressed in terms of local measurements. We also show that generation of entangled states in the atom-photon systems under consideration strongly depends on the choice of initial conditions and that the parasitic influence of cavity detuning can be compensated through the use of Kerr medium.

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M. Ali Can, Alexander A. Klyachko, Alexander S. Shumovsky. 2002-09-30. Entanglement and the SU(2) phase states in atomic systems. https://doi.org/10.1103/physreva.66.022111

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