Multipartite entanglement and high precision metrology

TL;DR

This paper explores how multipartite entanglement enhances phase estimation sensitivity in quantum metrology, establishing criteria based on quantum Fisher information and highlighting the necessity of genuine multipartite entanglement for optimal measurement precision.

Contribution

It introduces entanglement criteria linked to quantum Fisher information and demonstrates the essential role of genuine multipartite entanglement in achieving maximum metrological sensitivity.

Findings

Genuine multipartite entanglement is necessary for maximum phase sensitivity.

Entanglement criteria based on quantum Fisher information are effective.

Multipartite entanglement improves the precision of quantum measurements.

Abstract

We present several entanglement criteria in terms of the quantum Fisher information that help to relate various forms of multipartite entanglement to the sensitivity of phase estimation. We show that genuine multipartite entanglement is necessary to reach the maximum sensitivity in some very general metrological tasks using a two-arm linear interferometer. We also show that it is needed to reach the maximum average sensitivity in a certain combination of such metrological tasks.