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arXiv · 1203.0980

Experimental observation of impossible-to-beat quantum advantage on a hybrid photonic system

Eleonora Nagali·Vincenzo D'Ambrosio·Fabio Sciarrino·Adan Cabello
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Abstract

Quantum resources outperform classical ones for certain communication and computational tasks. Remarkably, in some cases, the quantum advantage cannot be improved using hypothetical postquantum resources. A class of tasks with this property can be singled out using graph theory. Here we report the experimental observation of an impossible-to-beat quantum advantage on a four-dimensional quantum system defined by the polarization and orbital angular momentum of a single photon. The results show pristine evidence of the quantum advantage and are compatible with the maximum advantage allowed using postquantum resources.

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Eleonora Nagali, Vincenzo D'Ambrosio, Fabio Sciarrino, Adan Cabello. 2012-03-05. Experimental observation of impossible-to-beat quantum advantage on a hybrid photonic system. https://doi.org/10.1103/physrevlett.108.090501

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