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arXiv · 2410.22635

Diffraction of correlated biphotons through transparent samples

Nazanin Dehghan·Alessio D'Errico·Yingwen Zhang·Benjamin Sussman·Ebrahim Karimi
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Abstract

Two-photon states generated through degenerate spontaneous parametric down-conversion (SPDC) can exhibit sharp correlations in the transverse spatial coordinates. This property leads to unique free-space propagation features. Here, we show that a phase object placed in the image plane of the source affects the free space propagation of the SPDC in a way that is mathematically analogous to the Fresnel diffraction of a first-order coherent source. This effect can be observed via the extraction of correlation images. We demonstrate this prediction with an experiment where the diffraction of correlated bi-photons is detected using an event-based camera. The results allow us to reconstruct the phase structure of the sample via non-interferometric phase retrieval methods. We verify that the retrieved phase patterns exhibit an enhanced contrast due to the probe two-photon nature. Our findings offer applications for non-interferometric, quantum-enhanced phase imaging.

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Nazanin Dehghan, Alessio D'Errico, Yingwen Zhang, Benjamin Sussman, Ebrahim Karimi. 2024-10-30. Diffraction of correlated biphotons through transparent samples. https://arxiv.org/abs/2410.22635

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