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arXiv:2211.08674 · Physical Review A

Multiphoton correlations between quantum images

Serge Massar, F. Devaux, Éric Lantz

Published Jul 13, 2023• 6 citations
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Abstract

Experimental demonstrations of entangled quantum images produced through parametric down conversion have so far been confined to studying two-photon correlations. Here we show that multiphoton correlations between quantum images are accessible experimentally and exhibit many new features including being sensitive to the phase of the biphoton wave function. As a concrete example, we consider a modification of existing quantum imaging experiments in which the charge-coupled device cameras are moved out of focus, provide detailed analytical predictions for the resulting four-photon interferences, and support these by numerical simulations. The proposed experiment can also be interpreted as entanglement swapping: Bob's photons are initially unentangled, but the joint detection of Alice's photons projects Bob's photons onto an entangled state. The general approach proposed here can be extended to other quantum optics experiments involving high-dimensional entanglement.

DOI
10.1103/physreva.108.013705

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Experimental demonstrations of entangled quantum images produced through parametric down conversion have so far been confined to studying two-photon correlations. Here we show that multiphoton correlations between quantum images are accessible experimentally and exhibit many new features including being sensitive to the phase of the biphoton wave function. As a concrete example, we consider a modification of existing quantum imaging experiments in which the charge-coupled device cameras are moved out of focus, provide detailed analytical predictions for the resulting four-photon interferences, and support these by numerical simulations. The proposed experiment can also be interpreted as entanglement swapping: Bob's photons are initially unentangled, but the joint detection of Alice's photons projects Bob's photons onto an entangled state. The general approach proposed here can be extended to other quantum optics experiments involving high-dimensional entanglement.
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Abstract We first extend our recent experiments of spatial quantum correlations imaging through thin scattering media to the case where two phase scattering plates placed respectively in the image and the Fourier planes of the biphoton source, mimics a thick scattering medium. Spatial correlations between twin photons are still detected at the quantum level but no more in the form of two-photon speckle-like patterns. However, we show that spatial entanglement of very-high dimensionality can be retrieved through thick scattering media with moderate losses and without any fair sampling assumption in the space and time domains. Second, a numerical simulation of the biphoton wave function is developed and applied to our experimental situation, with a good agreement.
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We report the results of two-photon quantum holography where spatial information stored in phase holograms is retrieved by measuring quantum spatial correlations between two images formed by spatially entangled twin photons with a Schmidt number of 450 in the two-dimensional transverse space. In our experiments, the entire flux of spontaneous down-converted photons illuminates the phase holograms and the photons of signal-idler pairs transmitted by the holograms are detected separately in the far field on two electron-multiplying charge coupled device cameras.