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arXiv · 2506.14300

Certifying spatial entanglement between non-degenerate photon pairs with a camera

Emma Brambila·Raphael Guitter·René Sondenheimer·Markus Gräfe·Hugo Defienne
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Abstract

We investigate transverse spatial entanglement between photon pairs of different wavelengths using a camera-based coincidence technique. By adapting the correlation measurements to the photons frequencies, we certify the presence of entanglement between the pairs through violation of an Einstein-Podolsky-Rosen criterion. Additionally, we examine how parameters such as pump waist and crystal length influence these correlations. Our results highlight key differences from the frequency-degenerate case, showing that an adapted theoretical analysis is essential to avoid significant misestimations and to reliably certify entanglement.

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Emma Brambila, Raphael Guitter, René Sondenheimer, Markus Gräfe, Hugo Defienne. 2025-06-17. Certifying spatial entanglement between non-degenerate photon pairs with a camera. https://doi.org/10.1364/ol.569692

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