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Quantum Nonlocality in Phase Space

Konrad Banaszek·Krzysztof Wodkiewicz
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Abstract

We propose an experiment demonstrating the nonlocality of a quantum singlet-like state generated from a single photon incident on a beam splitter. Each of the two spatially separated apparatuses in the setup performs a strongly unbalanced homodyning, employing a single photon counting detector. We show that the correlation functions violating the Bell inequalities in the proposed experiment are given by the joint two-mode Q-function and the Wigner function of the optical singlet-like state. This establishes a direct relationship between two intriguing aspects of quantum mechanics: the nonlocality of entangled states and the noncommutativity of quantum observables, which underlies the nonclassical structure of phase space quasidistribution functions.

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Konrad Banaszek, Krzysztof Wodkiewicz. 1998-06-21. Quantum Nonlocality in Phase Space. https://doi.org/10.1103/physrevlett.82.2009

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