Quantum correlations (QCs), including quantum entanglement and those different, are important quantum resources and have attracted much attention recently. Quantum entanglement swapping as a kernel technique has already been applied to quantum repeaters for successfully generating long-distance shared maximally entangled qubit states. Long-distance shared QCs containing shared entanglements are useful and important for some quantum information processing in future quantum networks. In this paper, the concept of quantum entanglement repeater is extended to that of QC repeater by generalizing quantum entanglement swapping to QC swapping. Specifically, the swapping of QCs in a pair of Werner states through a local bipartite von Neumann measurement is treated. Four different QC measures, i.e., entanglement of formation (William in Phys Rev Lett 80:2245, 1998), quantum discord (Ollivier and Zurek in Phys Rev Lett 88:017901, 2001), measurement-induced disturbance (MID) (Luo in Phys Rev A 77:022301, 2008) and ameliorated MID (Girolami et al. in J Phys A 44:352002, 2011), are employed to characterize and quantify QCs. Properties and thresholds of all QCs which occur in the swapping process are revealed, and two different phenomena are exposed and explained. It is found that a long-distance shared QC can be generated from two short-distance ones via QC swapping indeed; however, its amount cannot exceed the minimum one among the QCs in the two initial states and in the measuring state as far as the four quantifiers are concerned.
Quantum Information Processing – Springer Journals
Published: Nov 14, 2014
It’s your single place to instantly
discover and read the research
that matters to you.
Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.
All for just $49/month
Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly
Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.
All the latest content is available, no embargo periods.
“Whoa! It’s like Spotify but for academic articles.”@Phil_Robichaud