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arXiv · 2108.05346

Quantum microscopy based on Hong-Ou-Mandel interference

Bienvenu Ndagano·Hugo Defienne·Dominic Branford·Yash D. Shah·Ashley Lyons·Niclas Westerberg·Erik M. Gauger·Daniele Faccio
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Abstract

Hong-Ou-Mandel (HOM) interference, the bunching of indistinguishable photons at a beam splitter, is a staple of quantum optics and lies at the heart of many quantum sensing approaches and recent optical quantum computers. Here, we report a full-field, scan-free, quantum imaging technique that exploits HOM interference to reconstruct the surface depth profile of transparent samples. We demonstrate the ability to retrieve images with micrometre-scale depth features with a photon flux as small as 7 photon pairs per frame. Using a single photon avalanche diode camera we measure both the bunched and anti-bunched photon-pair distributions at the HOM interferometer output which are combined to provide a lower-noise image of the sample. This approach demonstrates the possibility of HOM microscopy as a tool for label-free imaging of transparent samples in the very low photon regime.

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Bienvenu Ndagano, Hugo Defienne, Dominic Branford, Yash D. Shah, Ashley Lyons, Niclas Westerberg, Erik M. Gauger, Daniele Faccio. 2021-08-11. Quantum microscopy based on Hong-Ou-Mandel interference. https://doi.org/10.1038/s41566-022-00980-6

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