Experimental distributed quantum sensing in a noisy environment

TL;DR

This paper experimentally demonstrates a quantum sensing protocol using entangled trapped-ion sensors that maintains high precision in noisy environments by exploiting spatial differences between signal and noise, outperforming classical strategies.

Contribution

The work provides the first experimental validation of a quantum sensing protocol that uses entanglement to distinguish signals from noise with different spatial profiles.

Findings

Quantum protocol outperforms classical strategies in noisy environments.

Entangled sensors effectively isolate signals from spatially varying noise.

Technique applicable to various fields and distances, suitable for quantum sensor networks.

Abstract

The precision advantages offered by harnessing the quantum states of sensors can be readily compromised by noise. However, when the noise has a different spatial function than the signal of interest, recent theoretical work shows how the advantage can be maintained and even significantly improved. In this work we experimentally demonstrate the associated sensing protocol, using trapped-ion sensors. An entangled state of multi-dimensional sensors is created that isolates and optimally detects a signal, whilst being insensitive to otherwise overwhelming noise fields with different spatial profiles over the sensor locations. The quantum protocol is found to outperform a perfect implementation of the best comparable strategy without sensor entanglement. While our demonstration is carried out for magnetic and electromagnetic fields over a few microns, the technique is readily applicable over arbitrary distances and for arbitrary fields, thus present a promising application for emerging quantum sensor networks.