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DOE OSTI · 2008382

At-wavelength characterization of X-ray wavefronts in Bragg diffraction from crystals

Shi, Xianbo (ORCID:0000000210699981)·Qiao, Zhi·Pradhan, Paresh·Liu, Peifan (ORCID:0000000273816153)·Assoufid, Lahsen·Kim, Kwang-Je (ORCID:0000000302159739)·Shvyd'ko, Yuri
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Abstract

The advent of next-generation synchrotron radiation sources and X-ray free-electron lasers calls for high-quality Bragg-diffraction crystal optics to preserve the X-ray beam coherence and wavefront. This requirement brings new challenges in characterizing crystals in Bragg diffraction in terms of Bragg-plane height errors and wavefront phase distortions. Here, a quantitative methodology to characterize crystal optics using a state-of-the-art at-wavelength wavefront sensing technique and statistical analysis is proposed. The method was tested at the 1-BM-B optics testing beamline at the Advanced Photon Source for measuring silicon and diamond crystals in a self-referencing single-crystal mode and an absolute double-crystal mode. The phase error sensitivity of the technique is demonstrated to be at the λ/100 level required by most applications, such as the characterization of diamond crystals for cavity-based X-ray free-electron lasers.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICSat-wavelength metrologycoded maskcrystal diffractionphase errorwavefront sensing

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Shi, Xianbo (ORCID:0000000210699981), Qiao, Zhi, Pradhan, Paresh, Liu, Peifan (ORCID:0000000273816153), Assoufid, Lahsen, Kim, Kwang-Je (ORCID:0000000302159739), Shvyd'ko, Yuri. 2023-10-10. At-wavelength characterization of X-ray wavefronts in Bragg diffraction from crystals. https://doi.org/10.1107/s1600577523007531

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