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arXiv · 2005.14696

Beyond coincidence: using all the data in Hong-Ou-Mandel interferometry

Hannah Scott·Dominic Branford·Niclas Westerberg·Jonathan Leach·Erik M. Gauger
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Abstract

The Hong-Ou-Mandel effect provides a mechanism to determine the distinguishability of a photon pair by measuring the bunching rates of two photons interfering at a beam splitter. Of particular interest is the distinguishability in time, which can be used to probe a time delay. Photon detectors themselves give some timing information, however--while that resolution may dwarf that of an interferometric technique--typical analyses reduce the interference to a binary event, neglecting temporal information in the detector. By modelling detectors with number and temporal resolution we demonstrate a greater precision than coincidence rates or temporal data alone afford. Moreover, the additional information can allow simultaneous estimation of a time delay alongside calibration parameters, opening up the possibility of calibration-free protocols and approaching the precision of the quantum Cram\'er-Rao bound.

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Hannah Scott, Dominic Branford, Niclas Westerberg, Jonathan Leach, Erik M. Gauger. 2020-05-29. Beyond coincidence: using all the data in Hong-Ou-Mandel interferometry. https://doi.org/10.1103/physreva.102.033714

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