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Quantum entanglement with acousto-optic modulators: 2-photon beatings and Bell experiments with moving beamsplitters

Andre Stefanov·Hugo Zbinden·Antoine Suarez·Nicolas Gisin
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Abstract

We present an experiment testing quantum correlations with frequency shifted photons. We test Bell inequality with 2-photon interferometry where we replace the beamsplitters by acousto-optic modulators, which are equivalent to moving beamsplitters. We measure the 2-photon beatings induced by the frequency shifts, and we propose a cryptographic scheme in relation. Finally, setting the experiment in a relativistic configuration, we demonstrate that the quantum correlations are not only independent of the distance but also of the time ordering between the two single-photon measurements.

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Andre Stefanov, Hugo Zbinden, Antoine Suarez, Nicolas Gisin. 2002-10-02. Quantum entanglement with acousto-optic modulators: 2-photon beatings and Bell experiments with moving beamsplitters. https://doi.org/10.1103/physreva.67.042115

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