Separability in terms of a single entanglement witness
2013 (English)In: Physical Review A. Atomic, Molecular, and Optical Physics, ISSN 1050-2947, E-ISSN 1094-1622, Vol. 88, no 1, 010301- p.Article in journal (Refereed) Published
The separability problem is formulated in terms of a characterization of a single entanglement witness. More specifically, we show that any (in general multipartite) state rho is separable if and only if a specially constructed entanglement witness W-rho is weakly optimal, i.e., its expectation value vanishes on at least one product vector. Interestingly, the witness can always be chosen to be decomposable. Our result changes the conceptual aspect of the separability problem and raises some questions about the properties of positive maps.
Place, publisher, year, edition, pages
2013. Vol. 88, no 1, 010301- p.
IdentifiersURN: urn:nbn:se:su:diva-92629DOI: 10.1103/PhysRevA.88.010301ISI: 000321269300001OAI: oai:DiVA.org:su-92629DiVA: diva2:641750