Optics for coherent X-ray applications

Abstract

Developments of X-ray optics for full utilization of diffraction-limited storage rings (DLSRs) are presented. The expected performance of DLSRs is introduced using the design parameters of SPring-8 II. To develop optical elements applicable to manipulation of coherent X-rays, advanced technologies on precise processing and metrology were invented. With propagation-based coherent X-rays at the 1 km beamline of SPring-8, a beryllium window fabricated with the physical-vapour-deposition method was found to have ideal speckle-free properties. The elastic emission machining method was utilized for developing reflective mirrors without distortion of the wavefronts. The method was further applied to production of diffraction-limited focusing mirrors generating the smallest spot size in the sub-10 nm regime. To enable production of ultra-intense nanobeams at DLSRs, a low-vibration cooling system for a highheat-load monochromator and advanced diagnostic systems to characterize X-ray beam properties precisely were developed. Finally, new experimental schemes for combinative nano-analysis and spectroscopy realised with novel X-ray optics are discussed.

Direct 2D spatial-coherence determination using the Fourier-analysis method: multi-parameter characterization of the P04 beamline at PETRA III

“…Spatial-coherence degradation stands for a reduction of the (effective) spatial degree of coherence of the photon beam, originating from diverse sources within the beamline or the experiment [25,54,55]. One has to distinguish between direct and indirect coherence degradation.…”

“…One important issue in this respect is whether the degree of coherence of the undulator beam can be transported without losses to these "coherent-flux-hungry" experiments. Beamline optics may cause a degradation of spatial coherence, e. g., due to imperfections of beryllium windows or of optics' surfaces, or vibrations of optical elements [23][24][25][26][27][28]. Another relevant question is how to determine the best beamline setting giving an optimized flux-coherence-balance of the beam for diverse experimental requirements.…”

Imaging of intracellular fatty acids by scanning X‐ray fluorescence microscopy

“…SXFM can now be used to image mitochondria at the organelle level (18). Moreover, greater sensitivity due to the use of higher numbers of photons produced by a synchrotron facility and higher resolution due to modification of the X‐ray focusing system are expected in the near future (22, 32, 33). Single‐element labeling of fatty acids combined with X‐ray fluorescence microscopy, in addition to chemical and biochemical procedures, should facilitate investigation of the intracellular dynamics of lipids.…”

Modelling phase imperfections in compound refractive lenses

“…Although a recent development, X-ray lenses are used at most high-energy synchrotron facilities 1 and X-ray Free-Electron Lasers (XFEL) either for beam conditioning, final focusing of the X-rays into the sample or for imaging. The recent development and establishment of fourth-generation synchrotron light sources -as upgrades of existing machines or the construction of new facilities -and the emergence of the XFEL poses a new challenge for X-ray optics: wavefront preservation, as at modern sources the X-ray beam quality at the sample is primarily limited by the optical quality (Schroer & Falkenberg, 2014;Yabashi et al, 2014).…”