A formalism for steering with local quantum measurements

Autor: Sainz, A. B., Aolita, L., Piani, M., Hoban, M. J., Skrzypczyk, P.
Rok vydání: 2017
Předmět:
Druh dokumentu: Working Paper
DOI: 10.1088/1367-2630/aad8df
Popis: We develop a unified approach to classical, quantum and post-quantum steering. The framework is based on uncharacterised (black-box) parties performing quantum measurements on their share of a (possibly unphysical) quantum state, and its starting point is the characterisation of general no-signalling assemblages via non-positive local hidden-state models. By developing a connection to entanglement witnesses, this formalism allows for new definitions of families of assemblages, in particular via (i) non-decomposable positive maps and (ii) unextendible product bases. The former proves to be useful for constructing post-quantum assemblages with the built-in feature of yielding only quantum correlations in Bell experiments, while the latter always gives certifiably post-quantum assemblages. Finally, our framework is equipped with an inherent quantifier of post-quantum steering, which we call the negativity of post-quantum steering. We postulate that post-quantum steering should not increase under one-way quantum operations from the steered parties to the steering parties, and we show that, in this sense, the negativity of post-quantum steering is a convex post-quantum-steering monotone.
Comment: 27 pages, 3 figures, one table. See related work by Matty J. Hoban and Ana Bel\'en Sainz, arxiv:1708.xxxxx. Comments welcome
Databáze: arXiv