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arXiv · 2603.16235

Two-Dimensional Far-Field Correlations of X-ray Photon Pairs

E. Strizhevsky·Y. Klein·R. Hartmann·S. Francoual·T. Schulli·T. Zhou·A. Sharma·U. Pietsch·L. Strüder D. Altamura·C. Giannini·M. Shokr·S. Shwartz
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Abstract

We directly observe far-field correlations of x-ray photon pairs generated by spontaneous parametric down-conversion (SPDC). Using an energy-resolved, two-dimensional photon counting detector we record the full ring-shaped emission of both photons across a broad bandwidth and extract pair correlations directly from raw events without imposing angular constraints. The ring radii scale with photon energy, in quantitative agreement with transverse phase matching, providing a stringent momentum-space validation of x-ray SPDC. These observations open a route to leveraging quantum correlations in x-ray imaging and metrology, including correlation-enhanced magnification and reduced blurring.

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E. Strizhevsky, Y. Klein, R. Hartmann, S. Francoual, T. Schulli, T. Zhou, A. Sharma, U. Pietsch, L. Strüder D. Altamura, C. Giannini, M. Shokr, S. Shwartz. 2026-03-17. Two-Dimensional Far-Field Correlations of X-ray Photon Pairs. https://arxiv.org/abs/2603.16235

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