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.
@article{arxiv.1510.08030,
title = {Quantification of Einstein-Podolski-Rosen steering for two-qubit states},
author = {A. C. S. Costa and R. M. Angelo},
journal= {arXiv preprint arXiv:1510.08030},
year = {2016}
}