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arXiv · 1502.04926

Loss-tolerant EPR steering for arbitrary dimensional states: joint measurability and unbounded violations under losses

Paul Skrzypczyk·Daniel Cavalcanti
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Abstract

We show how to construct loss-tolerant linear steering inequalities using a generic set of von Neumann measurements that are violated by $d$-dimensional states, and that rely only upon a simple property of the set of measurements used (the maximal overlap between measurement directions). Using these inequalities we show that the critical detection efficiency above which $n$ von Neumann measurements can demonstrate steering is $1/n$. We show furthermore that using our construction and high dimensional states allows for steering demonstrations which are also highly robust to depolarising noise and produce unbounded violations in the presence of loss. Finally, our results provide an explicit means to certify the non-joint measurability of any set of inefficient von Neuman measurements.

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Paul Skrzypczyk, Daniel Cavalcanti. 2015-08-13. Loss-tolerant EPR steering for arbitrary dimensional states: joint measurability and unbounded violations under losses. https://doi.org/10.1103/physreva.92.022354

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