An operational interpretation for multipartite entanglement

TL;DR

This paper provides an operational interpretation of pure-state multipartite entanglement through quantum estimation, linking it to the quantum Fisher information and local observable measurements.

Contribution

It introduces a novel operational interpretation of multipartite entanglement based on quantum estimation and relates it to measurable quantities.

Findings

Quantum Fisher information quantifies entanglement strength.

Multipartite entanglement measure expressed as local observable expectation.

Operational link established between estimation precision and entanglement.

Abstract

We introduce an operational interpretation for pure-state global multipartite entanglement based on quantum estimation. We show that the estimation of the strength of low-noise locally depolarizing channels, as quantified by the regularized quantum Fisher information, is directly related to the Meyer-Wallach multipartite entanglement measure. Using channels that depolarize across different partitions, we obtain related multipartite entanglement measures. We show that this measure is the sum of expectation values of local observables on two copies of the state.