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arXiv · 2309.00295

Local discrimination of orbital angular momentum in entangled states

Simone Cialdi·Edoardo Suerra·Samuele Altilia·Stefano Olivares·Bruno Paroli·Marco A. C. Potenza·Mirko Siano·Matteo G. A. Paris
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Abstract

We address the use of a calcite crystal-based local detector to the discrimination of orbital angular momentum of quantum radiation produced by parametric down conversion. We demonstrate that a discrimination can be obtained exploiting the introduction of a fine and controlled spatial shift between two replicas of the state in the crystals. We believe that this technology could be used for future development of long-distance quantum communication techniques, where information encoding is based on orbital angular momentum.

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Simone Cialdi, Edoardo Suerra, Samuele Altilia, Stefano Olivares, Bruno Paroli, Marco A. C. Potenza, Mirko Siano, Matteo G. A. Paris. 2023-09-01. Local discrimination of orbital angular momentum in entangled states. https://doi.org/10.1103/physreva.110.043701

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