Super-resolution quantum imaging at the Heisenberg limit

The Abbe–Rayleigh diffraction limit constrains spatial resolution for classical imaging methods. Quantum imagingexploits correlations between photons to reproduce structures with higher resolution. Quantum-correlatedN-photonstates were shown to potentially surpass the classical limit by a factor of 1∕N, corresponding to the Heisenberg limit,using a method known as optical centroid measurement (OCM). In this work, the theory of OCM is reformulated forits application in imaging. Using entangled photon pairs and a recently developed integrated time-resolving detectorarray, OCM is implemented in a proof-of-principle experiment that demonstrates the expected enhancement. Thoseresults show the relevance of entanglement for imaging at the Heisenberg limit.