Gaussian State-Based Quantum Illumination with Simple Photodetection

TL;DR

This paper demonstrates that Gaussian quantum illumination with simple photodetection outperforms classical methods in object detection, especially under high noise and low signal conditions, using a comprehensive Gaussian formalism and simulations.

Contribution

It shows quantum illumination's advantage with simple photodetection using Gaussian states, even in high noise and low signal scenarios, expanding practical quantum sensing applications.

Findings

Quantum illumination surpasses classical detection with simple photodetection.

Advantage persists under high thermal noise and low reflectivity.

Simulations confirm the practical benefits of quantum illumination.

Abstract

Proofs of the quantum advantage available in imaging or detecting objects under quantum illumination can rely on optimal measurements without specifying what they are. We use the continuous-variable Gaussian quantum information formalism to show that quantum illumination is better for object detection compared with coherent states of the same mean photon number, even for simple direct photodetection. The advantage persists if signal energy and object reflectivity are low and background thermal noise is high. The advantage is even greater if we match signal beam detection probabilities rather than mean photon number. We perform all calculations with thermal states, even for non-Gaussian conditioned states with negative Wigner functions. We simulate repeated detection using a Monte Carlo process that clearly shows the advantages obtainable.