Receiver Design to Harness Quantum Illumination Advantage

TL;DR

This paper presents a structured quantum-illumination receiver design that, combined with an entangled light transmitter, achieves a significant error-probability advantage over classical lidar in noisy, lossy environments, advancing quantum sensing technology.

Contribution

It provides the first explicit, feasible quantum-illumination receiver design that outperforms classical sensors in realistic low-brightness, noisy conditions.

Findings

Achieves up to 3 dB error-exponent advantage over classical lidar.

Demonstrates feasibility for proof-of-principle experiments.

First structured quantum-optical sensor design surpassing classical performance in relevant regimes.

Abstract

An optical transmitter that uses entangled light generated by spontaneous parametric downconversion (SPDC), in conjunction with an optimal quantum-optical receiver (whose implementation is not yet known) is in principle capable of obtaining up to a 6 dB gain in the error-probability exponent over the optimum-reception un-entangled coherent-state lidar to detect the presence of a far-away target subject to entanglement-breaking loss and noise in the free-space link [Lloyd'08, Tan'08]. We present an explicit design of a structured quantum-illumination receiver, which in conjunction with the SPDC transmitter is shown to achieve up to a 3 dB error-exponent advantage over the classical sensor. Apart from being fairly feasible for a proof-of-principle demonstration, this is to our knowledge the first structured design of a quantum-optical sensor for target detection that outperforms the comparable best classical lidar sensor appreciably in a low-brightness, lossy and noisy operating regime.