Suppressing Diffraction-Related Intensity Losses in Transmissive Single-Crystal X-ray Optics

Nataliya Klimova,Anatoly Snigirev,Oleksandr Yefanov,Irina Snigireva

doi:10.3390/cryst11121561

Abstract

The highest-quality X-ray optics can be made of single-crystal materials such as silicon, germanium, or, even better, diamond. Unfortunately, such X-ray optics have one drawback: diffraction losses or the “glitch effect”. This effect manifests itself as follows: at some energies of X-rays, the intensity of the transmitted beam drops due to the fact that some crystalline planes have satisfied the diffraction condition. Diffraction losses are usually observed in spectroscopic experiments when the energy of the X-rays changes in a certain range. However, this effect might also influence any experiment using X-rays, especially at higher energies. In this paper, we propose a method to overcome the glitch problem in transmissive optics. This is achieved using small rotations of the optical element. We describe the algorithm for “glitch-free” measurements in detail and the theory behind it.

Highlights

X-ray beams generated by new sources, such as free-electron lasers (FELs) and fourthgeneration synchrotrons, have outstanding brightness and coherence
The highest-quality X-ray optics can be made of single-crystal materials such as silicon, germanium, or, even better, diamond
Diffraction losses are usually observed in spectroscopic experiments when the energy of the X-rays changes in a certain range

Summary

Introduction

X-ray beams generated by new sources, such as free-electron lasers (FELs) and fourthgeneration synchrotrons, have outstanding brightness and coherence To deliver such a beam to the sample, the quality of the optics has to be very high. Single-crystal materials, such as silicon, germanium, or diamond, are of high quality, are robust, and are reproducible Such optics have one drawback: diffraction losses due to undesired Bragg/Laue scattering, which is usually termed the “glitch effect” [2]. This effect manifests itself as follows: at some energy of the incident X-rays, the transmitted (or diffracted, in the case of monochromators) beam intensity drops. For thick optical elements (for example some CRLs made of silicon or diamond), this effect can lead to almost zero transmitted intensity

Results

Discussion

Conclusion