Exploiting the potential of beam-compressing channel-cut monochromators for laboratory high-resolution small-angle X-ray scattering experiments

NÁDAŽDY, Peter, Jakub HAGARA, Matej JERGEL, Eva MAJKOVÁ, Petr MIKULÍK, Zdenko ZÁPRAŽNÝ, Dusan KORYTÁR and Peter ŠIFFALOVIČ. Exploiting the potential of beam-compressing channel-cut monochromators for laboratory high-resolution small-angle X-ray scattering experiments. Journal of Applied Crystallography. Chester: INT UNION CRYSTALLOGRAPHY, 2019, vol. 52, JUN 2019, p. 498-506. ISSN 0021-8898. Available from: https://dx.doi.org/10.1107/S1600576719003674.

Basic information

• Original name: Exploiting the potential of beam-compressing channel-cut monochromators for laboratory high-resolution small-angle X-ray scattering experiments
• Authors: NÁDAŽDY, Peter (703 Slovakia), Jakub HAGARA (703 Slovakia), Matej JERGEL (703 Slovakia), Eva MAJKOVÁ (703 Slovakia), Petr MIKULÍK (203 Czech Republic, guarantor, belonging to the institution), Zdenko ZÁPRAŽNÝ (703 Slovakia), Dusan KORYTÁR (703 Slovakia) and Peter ŠIFFALOVIČ (703 Slovakia).
• Edition: Journal of Applied Crystallography, Chester, INT UNION CRYSTALLOGRAPHY, 2019, 0021-8898.

Other information

• Original language: English
• Type of outcome: Article in a journal
• Field of Study: 10302 Condensed matter physics
• Country of publisher: United Kingdom of Great Britain and Northern Ireland
• Confidentiality degree: is not subject to a state or trade secret
• WWW: URL
• Impact factor: Impact factor: 2.995
• RIV identification code: RIV/00216224:14310/19:00110922
• Organization unit: Faculty of Science
• Doi: http://dx.doi.org/10.1107/S1600576719003674
• UT WoS: 000470824800002
• Keywords in English: X-ray beam collimation; channel-cut monochromators; ray-tracing simulations; small-angle X-ray scattering; grazing-incidence small-angle X-ray scattering; SAXS; GISAXS
• Tags: GISAXS, ray-tracing, rivok, x-ray optics
• Tags: International impact, Reviewed

Abstract

A systematic study of beam-compressing monolithic channel-cut monochromators (CCMs) with a V-shaped channel was performed. The CCMs were optimized in terms of a chosen output beam parameter for exploitation in laboratory high-resolution small-angle X-ray scattering (SAXS) and grazing-incidence SAXS (GISAXS) experiments. Ray-tracing simulations provided maps of particular Ge(220) CCM output beam parameters over the complete set of asymmetry angles of the two CCM diffractions. This allowed the design and fabrication of two dedicated CCMs, one optimized for maximum photon flux per detector pixel and the other for K-2 suppression. The output beam quality was tested in SAXS/GISAXS experiments on a commercial setup with a liquid-metal-jet Ga microfocus X-ray source connected to 2D collimating Montel optics. The performance of the CCM optimized for maximum photon flux per detector pixel was limited by the quality of the inner channel walls owing to a strongly asymmetric design. However, the CCM optimized for K-2 suppression exhibited an excellent resolution of 314nm in real space. This was further enhanced up to 524nm by a parallel Ge(220) CCM in the dispersive configuration at a still applicable output flux of 3x10(6)photons(-1). The 314nm resolution outperforms by more than 2.5x the upper resolution limit of the same setup with a pinhole collimator instead of the CCM. Comparative SAXS measurements on the same setup with a Kratky block collimator as an alternative to the CCM showed that the CCM provided more than one order higher transmittance at a comparable resolution or twice higher resolution at a comparable transmittance. These results qualify CCMs for a new type of integrated reflective-diffractive optics consisting of Gobel mirrors and V-shaped CCMs for the next generation of high-performance microfocus laboratory X-ray sources.