2013/11/30 by Paul Skrzypczyk, Miguel Navascues, Daniel Cavalcanti · 1 citation
Physics and Astronomy · #quant-ph
paper · pdf · doi:10.1103/physrevlett.112.180404
published as Phys. Rev. Lett. 112, 180404 (2014) · 9 pages, 1 figure. v2: One example (ex. (iv)) removed. One appendix (E) and one reference ([28]) added. V3: new example of one-way steering included, typos corrected, new references
arxiv created 2014/04/11 · arxiv updated 2014/05/12
Einstein-Podolsky-Rosen (EPR) steering is a form of bipartite quantum correlation that is intermediate between entanglement and Bell nonlocality. It allows for entanglement certification when the measurements performed by one of the parties are not characterised (or are untrusted) and has applications in quantum key distribution. Despite its foundational and applied importance, EPR steering lacks a quantitative assessment. Here we propose a way of quantifying this phenomenon and use it to study the steerability of several quantum states. In particular we show that every pure entangled state is maximally steerable, the projector onto the anti-symmetric subspace is maximally steerable for all dimensions, we provide a new example of one-way steering, and give strong support that states with positive-partial-transposition are not steerable.