Super-resolution quantum imaging at the Heisenberg limit

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