Monogamy of Quantum Discord by Multipartite Correlations

TL;DR

This paper establishes a monogamy inequality linking pairwise and multipartite quantum correlations using global quantum discord, applicable to pure and mixed states, and explores residual correlations.

Contribution

It introduces a new monogamy inequality for quantum discord based on multipartite correlations, expanding understanding of quantum correlation distribution.

Findings

Monogamy bound holds for pure and mixed states under certain conditions.

The inequality is demonstrated for specific multipartite states like Schmidt, W, and GHZ states.

Residual multipartite correlations can be analyzed using the proposed monogamy bound.

Abstract

We introduce a monogamy inequality for quantum correlations, which implies that the sum of pairwise quantum correlations is upper limited by the amount of multipartite quantum correlations as measured by the global quantum discord. This monogamy bound holds either for pure or mixed quantum states provided that bipartite quantum discord does not increase under discard of subsystems. We illustrate the monogamy behavior for multipartite pure states with Schmidt decomposition as well as for W-GHZ mixed states. As a by-product, we apply the monogamy bound to investigate residual multipartite correlations.