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arXiv · 1407.0144

Generation of tunable entanglement and violation of a Bell-like inequality between different degrees of freedom of a single photon

Adam Valles·Vincenzo D'Ambrosio·Martin Hendrych·Michal Micuda·Lorenzo Marrucci·Fabio Sciarrino·Juan P. Torres
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Abstract

We demonstrate a scheme to generate noncoherent and coherent correlations, i.e., a tunable degree of entanglement, between degrees of freedom of a single photon. Its nature is analogous to the tuning of the purity (first-order coherence) of a single photon forming part of a two-photon state by tailoring the correlations between the paired photons. Therefore, well-known tools such as the Clauser-Horne-Shimony-Holt (CHSH) Bell-like inequality can also be used to characterize entanglement between degrees of freedom. More specifically, CHSH inequality tests are performed, making use of the polarization and the spatial shape of a single photon. The four modes required are two polarization modes and two spatial modes with different orbital angular momentum.

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Adam Valles, Vincenzo D'Ambrosio, Martin Hendrych, Michal Micuda, Lorenzo Marrucci, Fabio Sciarrino, Juan P. Torres. 2014-11-24. Generation of tunable entanglement and violation of a Bell-like inequality between different degrees of freedom of a single photon. https://doi.org/10.1103/physreva.90.052326

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