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arXiv · 0807.2711

Entanglement swapping between spacelike separated atoms

Juan León·Carlos Sabín
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Abstract

We show a mechanism that projects a pair of neutral two-level atoms from an initially uncorrelated state to a maximally entangled state while they remain spacelike separated. The atoms begin both excited in a common electromagnetic vacuum, and the radiation is collected with a partial Bell-state analyzer. If the interaction time is short enough and a certain two-photon Bell state is detected after the interaction, a high degree of entanglement, even maximal, can be generated while one atom is outside the light cone of the other, for arbitrary large interatomic distances.

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Juan León, Carlos Sabín. 2008-07-17. Entanglement swapping between spacelike separated atoms. https://doi.org/10.1103/physreva.78.052314

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