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arXiv · 2104.06288

Defocused travelling-fringes in scanning triple-Laue x-ray interferometry

Carlo P. Sasso·Giovanni Mana·Enrico Massa
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Abstract

The measurement of the silicon lattice parameter by a separate-crystal triple-Laue x-ray interferometer is a key step for the kilogram realisation by counting atoms. Since the measurement accuracy is approaching nine significant digits, a reliable model of the interferometer operation is demanded to quantify or exclude systematic errors. This paper investigates both analytically and experimentally the effect of defocus (a difference between the splitter-to-mirror distance on the one hand and the analyser-to-mirror one on the other) on the phase of the interference fringes and the measurement of the lattice parameter.

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Carlo P. Sasso, Giovanni Mana, Enrico Massa. 2021-04-13. Defocused travelling-fringes in scanning triple-Laue x-ray interferometry. https://doi.org/10.1107/s1600576721007962

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