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arXiv · 1501.03332

Inequivalence of entanglement, steering, and Bell nonlocality for general measurements

Marco Túlio Quintino·Tamás Vértesi·Daniel Cavalcanti·Remigiusz Augusiak·Maciej Demianowicz·Antonio Acín·Nicolas Brunner
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Abstract

Einstein-Podolsky-Rosen steering is a form of inseparability in quantum theory commonly acknowledged to be intermediate between entanglement and Bell nonlocality. However, this statement has so far only been proven for a restricted class of measurements, namely projective measurements. Here we prove that entanglement, one-way steering, two-way steering and nonlocality are genuinely different considering general measurements, i.e. single round positive-operator-valued-measures. Finally, we show that the use of sequences of measurements is relevant for steering tests, as they can be used to reveal "hidden steering".

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Marco Túlio Quintino, Tamás Vértesi, Daniel Cavalcanti, Remigiusz Augusiak, Maciej Demianowicz, Antonio Acín, Nicolas Brunner. 2016-06-03. Inequivalence of entanglement, steering, and Bell nonlocality for general measurements. https://doi.org/10.1103/physreva.92.032107

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