Distributed Quantum Sensing

TL;DR

Distributed quantum sensing leverages entanglement among multiple sensors to surpass classical measurement limits, with protocols, experiments, and future prospects discussed from a quantum-information perspective.

Contribution

This review introduces the quantum-information framework for distributed quantum sensing, detailing protocols, experimental demonstrations, and future opportunities.

Findings

Entanglement enhances measurement sensitivity beyond SQL

Distributed sensing protocols have been experimentally demonstrated

Future applications include advanced measurement networks

Abstract

A plethora of applications hinge on a network or an array of sensors to undertake measurement tasks. A rule of thumb for sensing is that a collective measurement taken by $M$ independent sensors can improve the sensitivity by $1/\sqrt{M}$, known as the standard quantum limit (SQL). Quantum resources such as entanglement and squeezed light can be harnessed to surpass the SQL. Distributed quantum sensing is an emerging subject dedicated to investigating the performance gain enabled by entangled states shared by multiple sensors in tackling different measurement problems. This Review formulates distributed quantum sensing from a quantum-information perspective and describes distributed quantum sensing protocols and their experimental demonstrations. The applications enabled by distributed quantum sensing and an outlook for future opportunities will also be discussed.