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arXiv:1403.3828 · Physical Review A

Randomized graph states and their entanglement properties

Jun-Yi Wu, Matteo A. C. Rossi, Hermann Kampermann, Simone Severini B, L. C. Kwek, Chiara Macchiavello, Dagmar Bruß

Published May 30, 2014• 17 citations
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Abstract

A class of mixed multiqubit states that corresponds to a randomized version of graph states is introduced and entanglement features of these states are studied by investigating both bipartite and genuine multipartite entanglement.
DOI
10.1103/physreva.89.052335

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Monogamy of bipartite correlations leads, for arbitrary pure multiqubit states, to simple conditions able to indicate various types of multipartite entanglement by being capable of excluding the possibility of kkk separability.
Graph states are special multipartite entangled states that have been proven useful in a variety of quantum information tasks. We address the issue of characterizing and quantifying the genuine multipartite entanglement of graph states up to eight qubits. The entanglement measures used are the geometric measure, the relative entropy of entanglement, and the logarithmic robustness, have been proved to be equal for the genuine entanglement of a graph state. We provide upper and lower bounds as well as an iterative algorithm to determine the genuine multipartite entanglement.
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