Purified discord and multipartite entanglement

From Discord to Entanglement

Two prominent and widely studied notions of quantum correlations are discord and entanglement, with the latter occupying a central place in quantum information theory, while the former being regarded of marginal significance and even being criticized by some researchers, although the deep relations between them have been revealed in recent years. Discord and entanglement, being indistinguishabl...

Direct-dynamical entanglement-discord relations

In this article, by considering Bell-diagonal two-qubit initial states under local dynamics generated by the Phase Damping, Bit Flip, Phase Flip, BitPhase Flip, and Depolarizing channels, we report some elegant direct-dynamical relations between geometric measures of Entanglement and Discord. The complex scenario appearing already in this simplified case study indicates that a similarly simple ...

Title Genuine multipartite entanglement without multipartite correlations

Genuine Multipartite Entanglement without Multipartite Correlations.

Nonclassical correlations between measurement results make entanglement the essence of quantum physics and the main resource for quantum information applications. Surprisingly, there are n-particle states which do not exhibit n-partite correlations at all but still are genuinely n-partite entangled. We introduce a general construction principle for such states, implement them in a multiphoton e...

Detecting multipartite entanglement

Andrew C. Doherty, Pablo A. Parrilo, and Federico M. Spedalieri School of Physical Sciences, University of Queensland, St Lucia, Queensland 4072, Australia Institute for Quantum Information, California Institute of Technology, Pasadena, California 91125, USA Institut für Automatik, ETH Zentrum, CH-8092 Zürich, Switzerland Quantum Computing Technologies Group, Jet Propulsion Laboratory, Pasadena...