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arXiv · 1103.3962

Spin-orbit hybrid entanglement of photons and quantum contextuality

Ebrahim Karimi·Jonathan Leach·Sergei Slussarenko·Bruno Piccirillo·Lorenzo Marrucci·Lixiang Chen·Weilong She·Sonja Franke-Arnold·Miles J. Padgett·Enrico Santamato
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Abstract

We demonstrate electromagnetic quantum states of single photons and of correlated photon pairs exhibiting "hybrid" entanglement between spin and orbital angular momentum. These states are obtained from entangled photon pairs emitted by spontaneous parametric down conversion, by employing a $q$-plate for coupling the spin and orbital degrees of freedom of a photon. Entanglement and contextual quantum behavior (that is also non-local, in the case of photon pairs) is demonstrated by the reported violation of the Clauser-Horne-Shimony-Holt inequality. In addition a classical analog of the hybrid spin-orbit photonic entanglement is reported and discussed.

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Ebrahim Karimi, Jonathan Leach, Sergei Slussarenko, Bruno Piccirillo, Lorenzo Marrucci, Lixiang Chen, Weilong She, Sonja Franke-Arnold, Miles J. Padgett, Enrico Santamato. 2011-03-21. Spin-orbit hybrid entanglement of photons and quantum contextuality. https://doi.org/10.1103/physreva.82.022115

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