Multipartite fully-nonlocal quantum states

TL;DR

This paper introduces a method to identify fully-nonlocal quantum states in multipartite systems, including graph states and certain mixed states, expanding understanding of quantum correlations.

Contribution

It provides a general framework for characterizing multipartite nonlocality and identifies new classes of fully-nonlocal states, including graph states and tensor products of Smolin states.

Findings

All completely-connected graph states are multipartite fully-nonlocal.

The tensor product of five Smolin states is multipartite fully-nonlocal.

Conditions for a system to be fully-nonlocal are derived.

Abstract

We present a general method to characterize the quantum correlations obtained after local measurements on multipartite systems. Sufficient conditions for a quantum system to be fully-nonlocal according to a given partition, as well as being (genuinely) multipartite fully-nonlocal, are derived. These conditions allow us to identify all completely-connected graph states as multipartite fully-nonlocal quantum states. Moreover, we show that this feature can also be observed in mixed states: the tensor product of five copies of the Smolin state, a biseparable and bound entangled state, is multipartite fully-nonlocal.