Quantum image distillation

TL;DR

This paper demonstrates a method to separate quantum and classical images superimposed in a single measurement, enhancing quantum imaging and communication techniques by effectively distinguishing quantum signals from classical noise.

Contribution

The authors experimentally show near-perfect separation of quantum and classical images using intensity correlation measurements, a novel approach for quantum-classical image distinction.

Findings

Successful separation of quantum and classical images in a superimposed measurement

Use of intensity correlation measurements for image distillation

Potential applications in quantum imaging and secure communications

Abstract

Imaging with quantum states of light promises advantages over classical approaches in terms of resolution, signal-to-noise ratio and sensitivity. However, quantum detectors are particularly sensitive sources of classical noise that can reduce or cancel any quantum advantage in the final result. Without operating in the single-photon counting regime, we experimentally demonstrate distillation of a quantum image from measured data composed of a superposition of both quantum and classical light. We measure the image of an object formed under quantum illumination (correlated photons) that is mixed with another image produced by classical light (uncorrelated photons) with the same spectrum and polarisation and we demonstrate near-perfect separation of the two superimposed images by intensity correlation measurements. This work provides a novel approach to mix and distinguish information carried by quantum and classical light, which may be useful for quantum imaging, communications, and security.