A measure of multipartite entanglement with computable lower bounds    [PDF]

Yan Hong, Ting Gao, Fengli Yan
In this paper, we introduce a measure of multipartite entanglement, $k$-ME concurrence $C_{k-\mathrm{ME}}(\rho)$, which satisfies important characteristics of an entanglement measure. Two lower bounds on this measure are given. These lower bounds are experimentally implementable without quantum state tomography and are easily computable as no optimization or eigenvalue evaluation is needed. We illustrate detailed examples in which the given bounds perform better than other known detect criteria.
View original: http://arxiv.org/abs/1206.6669