Randomized Graph states and X-chains

Date/Time: Thu., 28th, August 2014 15:00~16:00 - (room 1901 (19F), National Institute of Informatics)

Speaker: Junyi Wu (Heinrich-Heine Universität Düsseldorf, Germany)

[Randomized graph states] We introduce a class of mixed multi-qubit states, that corresponds to a randomized version of graph states . It is shown that unitary equivalences are lost by randomization using a rank argument. We study the entanglement features of these states by investigating both bipartite and genuine multipartite entanglement. Bipartite entanglement is shown to be present as a randomized edge exists across the bipartition. The presence of multipartite entanglement is characterized by witness operators which are subsequently adapted to study non-local properties through the violation of suitable Bell inequalities. At the end we present results on the entanglement detection of particular randomized graph states.