Entanglement criteria and full separability of multi-qubit quantum states

TL;DR

This paper introduces an entanglement criterion to determine full separability of multi-qubit states, providing necessary and sufficient conditions for certain states and extending to bound entangled states beyond GHZ diagonal forms.

Contribution

The paper presents a new entanglement criterion that accurately identifies full separability and extends to bound entangled states, with numerical evidence supporting its effectiveness.

Findings

Criterion is necessary and sufficient for GHZ diagonal three-qubit states.

Estimates the volume of bound entangled states within this class.

Extends approach to non-GHZ diagonal bound entangled states.

Abstract

We introduce an entanglement criterion to exclude full separability of quantum states. We present numerical evidence that the criterion is necessary and sufficient for the class of GHZ diagonal three-qubit states and estimate the volume of bound entangled states within this class. Finally, we extend our approach to bound entangled states which are not GHZ diagonal.