Tunable kinoform x-ray beam splitter

TL;DR

This paper presents a tunable kinoform x-ray beam splitter capable of high efficiency and adjustable splitting ratios for multi-keV photons, with potential applications in advanced x-ray beam control and diagnostics.

Contribution

The authors demonstrate a novel kinoform-based x-ray beam splitter with tunable splitting ratios and high diffraction efficiency, overcoming limitations of traditional gratings.

Findings

Achieves up to 99.1% splitting ratio by tilting optics.

Demonstrates high diffraction efficiency of 62.6% at 12.4 keV.

Operates effectively in the 7.2-19 keV photon energy range.

Abstract

We demonstrate an x-ray beam splitter with high performances for multi-kilo-electron-volt photons. The device is based on diffraction on kinoform structures, which overcome the limitations of binary diffraction gratings. This beam splitter achieves a dynamical splitting ratio in the range 0-99.1% by tilting the optics and is tunable, here shown in a photon energy range of 7.2-19 keV. High diffraction efficiency of 62.6% together with an extinction ratio of 0.6% is demonstrated at 12.4 keV, with angular separation for the split beam of 0.5 mrad. This device can find applications in beam monitoring at synchrotrons, at x-ray free electron lasers for online diagnostics and beamline multiplexing and, possibly, as key elements for delay lines or ultrashort x-ray pulses manipulation.