Advancements in measuring photon time delay and manipulating quantum light.

Researchers at the University of Portsmouth have demonstrated the ultimate sensitivity allowed by quantum physics in measuring the time delay between two photons. By measuring their interference at a beam-splitter through frequency-resolving sampling measurements, the team has shown that unprecedented precision can be reached within current technology with an error in the estimation that can be further decreased by decreasing the photonic temporal bandwidth. This breakthrough has significant implications for a range of applications, including more feasible imaging of nanostructures, including biological samples, and nanomaterial surfaces, as well as quantum enhanced estimation based on frequency-resolved boson sampling in optical networks.