Entanglement on macroscopic scales in a resonantly laser-excited atomic ensemble

S. Camalet

doi:10.1103/physreva.91.032312

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arXiv · 1407.0944

Entanglement on macroscopic scales in a resonantly laser-excited atomic ensemble

S. Camalet

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Abstract

We show that two groups of slow two-level atoms in a weak resonant laser field, are entangled. The considered groups can be separated by a macroscopic distance, and be parts of a larger atomic ensemble. In a dilute regime, for two very distant groups of atoms, in a plane wave laser beam, we determine the maximum attainable entanglement negativity, and a laser intensity below which they are certainly entangled. They both decrease with increasing distance between the two groups, but increase with enlarging groups sizes. As a consequence, for given laser intensity, far separated groups of atoms are necessarily entangled if they are big enough.

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S. Camalet. 2015-03-04. Entanglement on macroscopic scales in a resonantly laser-excited atomic ensemble. https://doi.org/10.1103/physreva.91.032312

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