Bounds on mixed state entanglement

TL;DR

This paper derives a general explicit bound on bipartite NPT entanglement in mixed states based on mixedness, with implications for experimental measurement and connections to thermodynamics and quantum correlation monogamy.

Contribution

It introduces a new, general bound on bipartite NPT entanglement for mixed states based on mixedness, applicable in finite-dimensional systems.

Findings

Derived an explicit bound for bipartite NPT entanglement based on mixedness.

Connected thermodynamic features to quantum correlation monogamy.

Provided a physically clear explanation of recent related results.

Abstract

In the general framework of $d\times d$ mixed states, we derive an explicit bound for bipartite NPT entanglement based on the mixedness characterization of the physical system. The result derived is very general, being based only on the assumption of finite dimensionality. In addition it turns out to be of experimental interest since some purity measuring protocols are known. Exploiting the bound in the particular case of thermal entanglement, a way to connect thermodynamic features to monogamy of quantum correlations is suggested, and some recent results on the subject are given a physically clear explanation.