Advances in Extreme Ultraviolet and X-ray Optics and Optical Systems for Synchrotrons, Free Electron Lasers, Highly Harmonic Generations and Telescopes

Dear Colleagues,

In the last 10 years, the need for high power, tunable and coherent extreme ultraviolet (EUV) and X-ray advanced sources required by scientific needs of several fields of physics, chemistry and biology has boosted the development of free-electron lasers (FELs), fourth-generation synchrotrons and table-top highly harmonic generation (HHG) sources with immense benefit for the whole scientific community. FELs offer unprecedented levels of brightness with short pulses, polarization control and energy tunability, enabling new types of experiments that were previously impossible; fourth-generation synchrotrons can take advantage of a highly reduced divergence beam that is closer to the diffraction limit, allowing for better resolution in microscopy thanks to the high coherence; HHG sources provide tunable attosecond pulses up to the soft X-ray range, thus allowing researchers to study ultrafast dynamics and perform imaging. These advances are driving even more highly demanding specifications in  EUV/X-ray optics, with researchers developing new types of X-ray devices that can take full advantage of these new sources and allow for novel scientific outcomes. In parallel, the quality level of X-ray optics for telescopes has equally increased as regards their complexity and, nowadays, major advances in the field have been enabled thanks to novel technologies.

This Special Issue aims to present original state-of-the-art research articles dealing with EUV and X-ray optics for synchrotrons, FELs, and telescopes (X-ray satellites) within their applications. Specifically, papers dealing with simulations, design, and realization of novel optical elements and devices, their characterization and optimization, their commissioning, and their application in experiments showing their performance are welcome. Moreover, review and perspective papers dealing with specific optical elements (such as spectrometers, monochromators, etc.) and their upgrades are also welcome. The analysis from a theoretical point of view of important parameters, such as the preservation of the coherence of new light sources of 4th generation diffraction limited machines, in the interaction with the optical elements, and the study of the scattering effect from the mirror surfaces, especially in hard X-ray optical system, will certainly be considered. In particular, any theoretical speculations over the treatment of the partial coherence in the photon transport analysis, or different ways to evaluate the scattering effect from the complete mirror metrology characterization. Finally, we encourage expanding the current vision of EUV and X-ray optics by proposing novel elements for future developments.

Researchers are invited to submit their contributions to this Special Issue. Topics include, but are not limited to, the following:

• State of the art in the manufacturing and implementation of EUV/X-ray optics: mirrors, coatings and multi-layers, diffractive lenses, crystals and diffraction gratings, etc.
• State-of-the-art EUV/X-ray optical system: spectrometers, monochromators, pulse compressors, active optical systems, etc.
• Optical metrology: novel figure error and roughness characterization techniques, gratings’ groove characterization methods, cross-calibration between different laboratories; round-robin mirror campaign results.
• Beamlines: new design, upgrades, realization, commissioning.
• Instrumentation advances related to EUV/X-ray optics such as mechanical systems, mountings, diagnostics and the like.
• Experimental applications of novel EUV/X-ray optics and related results.
• Review/perspectives of novel instrumentation.
• Theory (preservation of the coherence, scattering effect from microroughness, wavefront analysis).
• Simulations: review of existing packages, novel codes (ray-tracing, physical optics, partial coherence), etc.
• Wavefront sensing methods, novel technologies and results.

Dr. Lorenzo Raimondi
Dr. Maurizio Vannoni
Dr. Cristian Svetina
Guest Editors

Manuscript Submission Information

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• extreme ultraviolet and X-ray optics and optical systems
• mirrors, gratings, diffractive lenses, spectrometers, monochromators
• beamlines and instrumentation
• simulation codes and theory