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arXiv · 1603.07861

Quantum steering inequality with tolerance for measurement-setting-errors: experimentally feasible signature of unbounded violation

Adam Rutkowski·Adam Buraczewski·Paweł Horodecki·Magdalena Stobińska
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Abstract

Quantum steering is a relatively simple test for quantumness of correlations, proving that the values of quantum-mechanical measurement outcomes come into being only in the act of measurement. By exploiting quantum correlations Alice can influence -- steer -- Bob's physical system in a way inaccessible in classical world, leading to violation of some inequalities. Demonstrating this and similar quantum effects for systems of increasing size, approaching even the classical limit, is a long-standing challenging problem. Here we provide experimentally feasible signature of unbounded violation of a steering inequality. We derive its universal form where tolerance for measurement-setting-errors is explicitly build-in by means of the Deutsch-Maassen-Uffink uncertainty relation. Then, generalizing the mutual unbiasedness, we apply the inequality to the multi-singlet and multi-particle bipartite Bell-state. However, the method is general and opens the possibility of employing multi-particle bipartite steering for randomness certification and development of quantum technologies, e.g.\ random access codes.

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Adam Rutkowski, Adam Buraczewski, Paweł Horodecki, Magdalena Stobińska. 2016-03-25. Quantum steering inequality with tolerance for measurement-setting-errors: experimentally feasible signature of unbounded violation. https://doi.org/10.1103/physrevlett.118.020402

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