SIGNAL (programming language)

Quantum mechanics

Reflection (computer programming)

Computer science

Photon

Laser

Physics

Four-wave mixing

Optics

Image (mathematics)

Nonlinear optics

Artificial intelligence

Quantum

Programming language

Noise (video)

Physical review. A/Physical review, A

We investigate the use of correlated photon pair sources for the improved quantum-level detection of a target in the presence of a noise background. Photon pairs are generated by spontaneous four-wave mixing, one photon from each pair (the herald) is measured locally while the other (the signal) is sent to illuminate the target. Following diffuse reflection from the target, the signal photons are detected by a receiver and non-classical timing correlations between the signal and herald are measured in the presence of a configurable background noise source. Quantum correlations from the photon pair source can be used to provide an enhanced signal-to-noise ratio when compared to a classical light source of the same intensity.

Quantum-enhanced standoff detection using correlated photon pairs