All-optical Loss-tolerant Distributed Quantum Sensing

TL;DR

This paper introduces an all-optical, loss-tolerant distributed quantum sensing scheme that uses phase-sensitive amplifiers and interferometers to achieve near-optimal sensitivity, overcoming limitations of traditional methods.

Contribution

It presents a novel all-optical approach utilizing high-gain optical parametric amplifiers for loss-tolerant, high-bandwidth quantum sensing, compatible with current photonic technology.

Findings

Achieves sensitivity close to the quantum Fisher information limit.

Demonstrates robustness against high photon loss levels.

Offers advantages over conventional balanced homodyne detection.

Abstract

Distributed quantum sensing (DQS) leverages quantum resources to estimate an unknown global property of a networked quantum sensor beyond the classical limit. We propose and analyze an all-optical resource-efficient scheme for the next-generation DQS systems. Our method utilizes phase-sensitive optical parametric amplifiers and linear interferometers and achieves the sensitivity close to the optimal limit, as determined by the quantum Fisher information of the entangled resource state. Furthermore, it utilizes high-gain OPA-assisted detection, offering critical advantages of increased bandwidth and loss tolerance, in contrast to conventional methods employing balanced homodyne detection (BHD). We show the efficacy of our proposal for displacement sensing and show its loss tolerance against high levels of photon loss, thus circumventing the major obstacle in current BHD-based approaches. Our architectural analysis shows that our scheme can be realized with current quantum photonic technology