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arXiv · 1304.2527

Extreme spin squeezing for photons

Morgan W. Mitchell·Federica A. Beduini
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Abstract

We apply spin-squeezing techniques to identify and quantify highly multi-partite photonic entanglement in polarization-squeezed light. We consider a practical single-mode scenario, and find that Wineland-criterion polarization squeezing implies entanglement of a macroscopic fraction of the total photons. A Glauber-theory computation of the observable N-photon density matrix, with N up to 100, finds that N-partite entanglement is observable despite losses and without post-selection. We estimate that existing detectors could observe $\sim1000$-partite entanglement from a few dB of polarization squeezing.

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Morgan W. Mitchell, Federica A. Beduini. 2014-06-10. Extreme spin squeezing for photons. https://doi.org/10.1088/1367-2630%2F16%2F7%2F073027

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