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arXiv · 2411.12702

X-ray Phase Measurements by Time-Energy Correlated Photon Pairs

Yishai Klein·Edward Strizhevsky·Haim Aknin·Moshe Deutsch·Eliahu Cohen·Avi Pe'er·Kenji Tamasaku·Tobias Schulli·Ebrahim Karimi·Sharon Shwartz
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Abstract

The invention of X-ray interferometers has led to advanced phase-sensing devices that are invaluable in various applications. These include the precise measurement of universal constants, e.g. the Avogadro number, of lattice parameters of perfect crystals, and phase-contrast imaging, which resolves details that standard absorption imaging cannot capture. However, the sensitivity and robustness of conventional X-ray interferometers are constrained by factors, such as fabrication precision, beam quality, and, importantly, noise originating from external sources or the sample itself. In this work, we demonstrate a novel X-ray interferometric method of phase measurement with enhanced immunity to various types of noise, by extending, for the first time, the concept of the SU(1,1) interferometer into the X-ray regime. We use a monolithic silicon perfect crystal device with two thin lamellae to generate correlated photon pairs via spontaneous parametric down-conversion (SPDC). Arrival time coincidence and sum-energy filtration allow a high-precision separation of the correlated photon pairs, which carry the phase information from orders-of-magnitude larger uncorrelated photonic noise. The novel SPDC-based interferometric method presented here is anticipated to exhibit enhanced immunity to vibrations as well as to mechanical and photonic noise, compared to conventional X-ray interferometers. Therefore, this SU(1,1) X-ray interferometer should pave the way to unprecedented precision in phase measurements, with transformative implications for a wide range of applications.

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Yishai Klein, Edward Strizhevsky, Haim Aknin, Moshe Deutsch, Eliahu Cohen, Avi Pe'er, Kenji Tamasaku, Tobias Schulli, Ebrahim Karimi, Sharon Shwartz. 2024-11-19. X-ray Phase Measurements by Time-Energy Correlated Photon Pairs. https://arxiv.org/abs/2411.12702

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