Genuine multipartite nonlocality of entangled thermal states

TL;DR

This paper investigates the quantum nonlocality of multipartite entangled thermal states, demonstrating their potential for quantum communication despite thermal noise and detection inefficiencies, and providing generation schemes.

Contribution

It introduces a detailed analysis of multipartite entangled thermal states' nonlocality and discusses conditions for maximizing Bell inequality violations under realistic conditions.

Findings

Multipartite entangled thermal states violate Bell-like inequalities.

Such states can be robust against thermal noise and detection inefficiencies.

The paper proposes feasible generation schemes for these states.

Abstract

We assess quantum non-locality of multiparty entangled thermal states by studying, quantitatively, both tripartite and quadripartite states belonging to the Greenberger-Horne-Zeilinger (GHZ), W and linear cluster-state classes and showing violation of relevant Bell-like inequalities. We discuss the conditions for maximizing the degree of violation against the local thermal character of the states and the inefficiency of the detection apparatuses. We demonstrate that such classes of multipartite entangled states can be made to last quite significantly, notwithstanding adverse operating conditions. This opens up the possibility for coherent exploitation of multipartite quantum channels made out of entangled thermal states. Our study is accompanied by a detailed description of possible generation schemes for the states analyzed.