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arXiv · 1510.08030

Quantification of Einstein-Podolski-Rosen steering for two-qubit states

A. C. S. Costa·R. M. Angelo
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Abstract

In the last few years, several criteria to identify Eistein-Podolski-Rosen steering have been proposed and experimentally implemented. On the operational side, however, the evaluation of the steerability degree of a given state has shown to be a difficult task and only a few results are known. In this work, we propose a measure of steering that is based on the maximal violation of well established steering inequalities. Applying this approach to two-qubit states, we managed to derive simple closed formulas for steering in the two- and three-measurement scenarios. Among the options investigated, a measure has been found that correctly satisfies the entanglement-steering-nonlocality hierarchy and reproduces results reported so far.

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A. C. S. Costa, R. M. Angelo. 2016-02-19. Quantification of Einstein-Podolski-Rosen steering for two-qubit states. https://doi.org/10.1103/physreva.93.020103

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