Measurement-base-independent test for genuine multipartite entanglement

Abstract

We investigate a priori detection probabilities of genuine multipartite entanglement (GME). Even if one does not have knowledge of the basis in which a state is produced by a source, how a channel decoheres it or of the very working of the detectors used, we find that it is possible to detect GME with reasonably high probability in a feasible fashion. We show that by means of certain separability criteria, GME can be detected in a measurement-base-independent way. Our method provides several applications whenever e.g. state tomography is not possible or too demanding, and is a tool to investigate security issues in multi-particle quantum cryptographical protocols.