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arXiv · 2112.12102

Ultimate quantum sensitivity in the estimation of the delay between two interfering photons through frequency-resolving sampling

Danilo Triggiani·Giorgos Psaroudis·Vincenzo Tamma
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Abstract

We demonstrate the ultimate sensitivity allowed by quantum physics in the estimation of the time delay between two photons by measuring their interference at a beam-splitter through frequency-resolving sampling measurements. This sensitivity can be increased quadratically by decreasing the photonic temporal bandwidth even at values smaller than the time delay when standard two-photon interferometers become inoperable and without adapting the path of the reference photon, nor the need of time-resolving detectors with an unfeasible high resolution. Applications can range from more feasible imaging of nanostructures, including biological samples, and nanomaterial surfaces to quantum enhanced estimation based on frequency-resolved boson sampling in optical networks.

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Danilo Triggiani, Giorgos Psaroudis, Vincenzo Tamma. 2021-12-22. Ultimate quantum sensitivity in the estimation of the delay between two interfering photons through frequency-resolving sampling. https://doi.org/10.1103/physrevapplied.19.044068

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