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arXiv · 1701.02454

Enhanced violations of Leggett-Garg inequalities in an experimental three-level system

Kunkun Wang·Clive Emary·Xiang Zhan·Zhihao Bian·Jian Li·Peng Xue
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Abstract

Leggett-Garg inequalities are tests of macroscopic realism that can be violated by quantum mechanics. In this letter, we realise photonic Leggett-Garg tests on a three-level system and implement measurements that admit three distinct measurement outcomes, rather than the usual two. In this way we obtain violations of three- and four-time Leggett-Garg inequalities that are significantly in excess of those obtainable in standard Leggett-Garg tests. We also report violations the quantum-witness equality up to the maximum permitted for a three-outcome measurement. Our results highlight differences between spatial and temporal correlations in quantum mechanics.

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Kunkun Wang, Clive Emary, Xiang Zhan, Zhihao Bian, Jian Li, Peng Xue. 2017-01-10. Enhanced violations of Leggett-Garg inequalities in an experimental three-level system. https://doi.org/10.1364/oe.25.031462

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