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arXiv · quant-ph/9908082

A single atom in free space as a quantum aperture

S. J. van Enk·H. J. Kimble
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Abstract

We calculate exact 3-D solutions of Maxwell equations corresponding to strongly focused light beams, and study their interaction with a single atom in free space. We show how the naive picture of the atom as an absorber with a size given by its radiative cross section $σ=3λ^{2}/2π$ must be modified. The implications of these results for quantum information processing capabilities of trapped atoms are discussed.

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S. J. van Enk, H. J. Kimble. 1999-08-27. A single atom in free space as a quantum aperture. https://doi.org/10.1103/physreva.61.051802

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