FERMI, the Italian Free Electron Laser user facility, provides VUV/soft x-ray photons pulses with unprecedented high brilliance and coherence. The unique design of EIS-TIMER is conceived to exploit such kind of non-linear coherent experiments to probe collective vibrational and electronic properties of matter at the nanoscale. After the proof of principle experiment successfully carried out at the DiProI beamline employing a simplified and compact setup (mini-TIMER), the EIS-TIMER beamline has been installed and commissioned. The beamlines employs 24 mirrors and three photon beams in order to create a wide set of transient grating able to reach Q vectors so far impossible to probe. In the presentation the scientific case, the commissioning results as well as the future development of the beamline will be shown. The future project nano-TIMER will be described in detail with particular attention to it's unique optical scheme mainly composed by diffraction gratings.

SACLA was inaugurated in March 2012 with two beamlines: BL3 for hard X-ray FEL and BL1 for wide range spontaneous emission. Currently, all user experiments have been performed at BL3 and BL2 that was constructed as the second hard XFEL beamline. To enhance research opportunities with softer X-ray FEL, we decided to relocate the SCSS test accelerator, which was a prototype of SACLA and decommissioned in 2013, to the SACLA undulator hall, to connect to BL1, and to generate EUV and soft X-ray FEL independently of the SACLA linac. In addition, we started commissioning of the upgraded BL1 in September 2015, and successfully observe SASE lasing at a photon energy of 36 eV in October. We are now constructing the end station, and will start commissioning in June 2016. We will install two C-band accelerator units that increase an electron beam energy up to 750 MeV with a photon energy up to 100 eV in the summer of 2016. In this presentation, I will report the latest status of the beamline.

The BEaTriX (Beam Expander Testing X-ray facility) project is an X-ray apparatus under construction at INAF/OAB to generate a broad (200´60 mm2), uniform and low-divergent X-ray beam within a small lab (6´15 m²). BEaTriX will consist of an X-ray source in the focus a grazing incidence paraboloidal mirror to obtain a parallel beam, followed by a crystal monochromation system and by an asymmetrically-cut diffracting crystal to perform the beam expansion to the desired size. Once completed, BEaTriX will be used to directly perform the quality control of focusing modules of large X-ray optics such as those for the ATHENA X-ray observatory, based on either Silicon Pore Optics (baseline) or Slumped Glass Optics (alternative), and will thereby enable a direct quality control of angular resolution and effective area on a number of mirror modules in a short time, in full X-ray illumination and without being affected by the finite distance of the X-ray source. However, since the individual mirror modules for ATHENA will have an optical quality of 3-4 arcsec HEW or better, BEaTriX is required to produce a broad beam with divergence below 1-2 arcsec, and sufficient flux to quickly characterize the PSF of the module without being significantly affected by statistical uncertainties. Therefore, the optical components of BEaTriX have to be selected and/or manufactured with excellent optical properties in order to guarantee the final performance of the system. In this paper we report the final design of the facility and a detailed performance simulation.

Recently it was found that reflection gratings of standard quality, which can be used at lower energy soft X-rays with photon energies of the order of 300 eV, diffract also efficiently X-rays with photon energies of the order of 5 keV, when these gratings are operated at grazing angle of incidence in the extreme off-plane configuration [1]. Consequently a grating employed in the extreme off-plane configuration has the capability to provide monochromatic radiation in the photon energy range from below 1 keV to far above 2 keV, where one usually switches for the same purpose between the diffraction at surface structures and the diffraction in bulk structures. Such an operation scheme requires rather complex mechanical structures. The present study will show that the tuning of diffraction gratings in the conical diffraction configuration can cover the indicated and even more extended tuning ranges employing a rather simple mechanical structure. Infact such a grating can be mounted together with a plane mirror in a pseudo channel-cut crystal monochromator configuration, i.e. with almost parallel surfaces and with fixed gap between them. The photon energy is then tuned simply by varying the angle of grazing incidence onto the pair of optics. Like in a double crystal monochromator scheme the monochromatic beam will exit from the configuration parallel to the incident beam with in most cases negligibly varying displacement in the plane of incidence. The optical performance data will be discussed depending on the properties of some state-of-the-art synchrotron radiation sources. [1] W. Jark and D. Eichert, Opt. Express 23, 22753 (2015).

A blazed diffraction grating for the EUV lithography Beamline 12.0.1 of the Advanced Light Source has been fabricated using optical direct write lithography and anisotropic wet etching technology. A variable line spacing pattern was recorded on a photoresist layer and transferred to a hard mask layer of the grating substrate by a plasma etch. Then anisotropic wet etching was applied to shape triangular grating grooves with precise control of the ultralow blaze angle. Variation of the groove density along the grating length was measured with a Long Trace Profiler (LTP). Fourier analysis of the LTP data confirmed high groove placement accuracy of the grating. The grating coated with a Ru coating demonstrated diffraction efficiency of 69.6% in the negative first diffraction order which is close to theoretical efficiency at the wavelength of 13.5 nm. This work demonstrates an alternative approach to fabrication of highly efficient and precise x-ray diffraction gratings with ultra-low blaze angles.

Multilayer mirrors (MLM) with narrow spectral bandwidth are important for X-ray spectroscopy and imaging experiments in order to improve the spectral resolution. To overcome the bandwidth limit of conventional multilayers, single order lamellar multilayer grating (LMG) is one of the most promising methods. Driven by the high resolution spectroscopy for the plasma diagnosis at E=~1keV, single order LMG based on MoSi2/Si multilayer is developed. The multilayer period is 5.0 nm, with the Si thickness ratio of 0.6. An LMG with 600 nm grating period and 1:2 line-to-space ratio is designed. As it works at the single order diffraction regime, the 0th order peak reflectance (in theory) of the LMG is 45.4% at E=1.2 keV, which is the same as the multilayer mirror. The bandwidth can be reduced by 3 times compared to the planar multilayer. To demonstrate this LMG structure, MoSi2/Si multilayers have been deposited using direct current magnetron sputtering. Deep reactive ion etching technique is under optimization in order to produce the multilayer grating structure with a high aspect-ratio of around 5.

X-ray echo spectroscopy, a counterpart of neutron spin-echo, was recently introduced [1] to overcome limitations in spectral resolution and weak signals of the traditional inelastic x-ray scattering (IXS) probes. An image of a point-like x-ray source is defocused by a dispersing system comprised of asymmetrically cut specially arranged Bragg diffracting crystals. The defocused image is refocused into a point (echo) in a time-reversal dispersing system. If the defocused beam is inelastically scattered from a sample, the echo signal acquires a spatial distribution, which is a map of the inelastic scattering spectrum. The spectral resolution of the echo spectroscopy does not rely on the monochromaticity of the x-rays, ensuring strong signals along with a very high spectral resolution. Particular schemes of x-ray echo spectrometers for 0.1-meV and 0.02-meV ultra-high-resolution IXS applications (resolving power > 10^8) with broadband ~5-13 meV dispersing systems will be presented featuring more than 1000-fold signal enhancement. The technique is general, applicable in different photon frequency domains.\\ [1.] Yu. Shvyd’ko, Phys. Rev. Lett. 116, accepted (2016), arXiv:1511.01526.

A concept of an inelastic x-ray scattering (IXS) spectrograph with an imaging analyzer was proposed recently and discussed in a number of publications (see e.g. Ref.1). The imaging analyzer as proposed combines x-ray lenses with highly dispersive crystal optics. It allows conversion of the x-ray energy spectrum into a spatial image with very high energy resolution. However, the presented theoretical analysis of the spectrograph did not take into account details of the scattered radiation source, i.e. sample, and its impact on the spectrograph performance. Using numerical simulations we investigated the influence of the finite sample thickness, the scattering angle and the incident energy detuning on the analyzer image and the ultimate resolution.

We report on the manufacturing and X-ray tests of bent diamond-crystal X-ray spectrographs, designed for noninvasive diagnostics of the X-ray free-electron laser (XFEL) spectra in the spectral range from 5 to 15 keV. The key component is a curved, 20-μm thin, single crystalline diamond triangular plate in the (110) orientation. The radius of curvature can be varied between R = 0:6 m and R = 0:1 m in a controlled fashion, ensuring imaging in a spectral window of up to 60 eV for ~ 8 keV X-rays. All of the components of the bending mechanism (about 10 parts) are manufactured from diamond, thus ensuring safe operations in intense XFEL beams. The spectrograph is transparent to 88% for 5-keV photons, and to 98% for 15-keV photons. Therefore, it can be used for noninvasive diagnostics of the X-ray spectra during XFEL operations.

Ultra-thin (< 100 um) diamond single crystals are essential for the realization of numerous next generation x-ray optical devices. Fabrication and handling of such ultra-thin crystal components without introducing damage and strain is a challenge. Drumhead crystals, monolithic crystal structures comprised of a thin membrane furnished with a surrounding solid collar would be a solution for the proper handling ensuring mechanically stable and strain-free mount of the membranes with efficient thermal transport. However, diamond being one of the hardest and chemically inert materials poses insurmountable difficulties in the fabrication. Here we report on a successful manufacturing of the diamond drumhead crystals using picosecond laser milling. Subsequent temperature treatment appears to be crucial for the membranes to become defect-free and unstrained, as revealed by x-ray double-crystal topography on an example of drumhead crystals with 1-mm in diameter and 28 um to 47 um-thick membranes in the (100) orientation.

Several single crystal CVD diamonds with (001) and (111) surface orientations were studied using x-ray diffraction rocking curve mapping in the double-crystal pseudo plane-wave configuration using Bragg reflection geometry. Strongly nonuniform distributions of rocking curve parameters on the studied crystal surfaces were observed, which indicates that the crystals exhibit substantial lattice distortions. Selected crystal pairs were tested in the nondispersive double-crystal configuration using polychromatic bending magnet synchrotron radiation. The results suggest that CVD diamond crystals could be used as high-flux broadband x-ray monochromators in applications where preservation of the radiation wavefront is not a primary goal.

Multilayer monochromators are widely needed in synchrotron beamlines to provide the high photon flux as compared to crystals. Ru/B4C multilayer is the most promising candidate working at the energy region of 10-20 keV. To develop this multilayer monochromator for an undulator beamline with high power density, the layer structure and reflectivity of the multilayer were studied. The deposition process for the Ru/B₄C multilayers was first optimized. Multilayers with different periods (d=2.0 nm, 3.0 nm, 4.0 nm) and single layers fo Ru and B4C were fabricated and characterized using the grazing incidence X-ray reflectometry (GIXR). A low density of Ru in the multilayers was found as compared to the single layers which attributed to the relatively low reflectance of 53.3% at 8.05 keV of the multilayer with 3.0 nm period.

X-ray imaging of the laser produced plasma plays an important role in plasma diagnostics. Based on the urgent needs of conducting deeper and finer physical experiments, we developed a high-energy Kirkpatrick Baez microscope working at 17.48keV with a spectral resolution (E/▵E) of ~30. The concave spherical substrates was polished, ultrasonically cleaned and coated. The substrates have a radius of curvature of 20m with a roughness better than 0.3nm. The grazing incidence angles are designed at 0.7° and 0.73° for separate reflecting mirrors. The x-ray backlit imaging experiments show its spatial resolution is ~5.5μm at best focus. The effective field of view is measured to be ~90μm, which is consistent with the multilayer design. This article provides detailed informations for the optical design, multilayers coating and characterization of the microscope. The microscope promises to be a high-energy, high-resolution, and energy resolved X-ray diagnostics instrument for SG series laser facility.

The growing interest in the study of the extreme ultraviolet (EUV) radiation-matter interaction is feeding up the development of new technologies able to overcame some current technological limits. Adaptive optics is an established technology already widely used for wavefront correction in many applications such as astronomical telescopes, laser communications, high power laser systems, microscopy and high resolution imaging systems. Although this technology is already exploited in the EUV and X-ray range, its usage is only feasible in systems with a grazing incidence configuration. On the other hand, the development of a EUV normal incidence adaptive optics can open new interesting possibilities in many different fields ranging from free electron laser and synchrotron applications up to EUV photolithography. In this work we report the preliminary results achieved in the developing of a normal incidence EUV multilayered adaptive mirror tuned at 30.4nm. The proper functioning and potential applications of such device have been demonstrated by using a High order Harmonics Generation (HHG) source.

High resolution imagery of solar X-ray corona provides a crucial key to understand dynamics and heating processes of plasmas there. However, imagery of the Sun with sub-arcsecond resolution in X-ray wavelengths has never been conducted due to severe technical difficulty in fabricating precision Wolter mirrors with a wide field of view exceeding several 100”. For future X-ray observations of the Sun, we are attempting to realize precision Wolter mirrors with sub-arcsecond resolution by adopting state-of-the-art surface polish and measurement methods to segmented mirrors which consist of a portion of an entire circle. Following evaluation of X-ray focusing performance of the first engineering Wolter mirror using BL29XUL coherent X-ray beam line at SPring-8 synchrotron facility, the second engineering mirror was fabricated with improvements in precision polish from the first mirror incorporated. X-ray evaluation of the second mirror at SPring-8 was conducted in February 2015, yielding FWHM size of ~0.2” for the PSF core at 8 keV while its HPD (half power diameter) size still remained at ~3” due to a large amount of small-angle scattering right outside the PSF core. Further improvements in the precision polish for the second mirror, in particular in the spatial scale from 0.3 mm to 5 mm, is currently under way with another X-ray evaluation at SPring-8 planned in spring 2016. Progress in our development activities for precision Wolter mirrors will be reported including at-wavelength evaluation results.

Nickel is the unique material in the X-ray telescopes. And it has the typical soft material characteristics with low hardness、high surface damage and low stability of thermal. The traditional fabrication techniques are exposed to lots of problems, including great surface scratches, high sub-surface damage and poor surface roughness and so on. The current fabrication technology for the nickel aspheric mainly adopt the single point diamond turning(SPDT), which has lots of advantages such as high efficiency, ultra-precision surface figure, low sub-surface damage and so on. But the residual surface texture of SPDT will cause great scattering losses and fall far short from the requirement in the X-ray applications. This paper mainly investigates the magnetorheological finishing (MRF) techniques for the super-smooth processing on the nickel optics. Through the study of the MRF polishing techniques, we obtained the ideal super-smooth polishing technique based on the self-controlled MRF-fluid NS-1, and finished the high-precision surface figure lower than RMS λ/80 (λ=632.8nm) and super-smooth roughness lower than Ra 0.3nm on the plane reflector and roughness lower than Ra 0.4nm on the convex cone. The studying of the MRF techniques makes a great effort to the state-of-the-art nickel material processing level for the X-ray optical systems applications.

Publisher’s Note: This conference presentation, originally published on 2 November 2016, was withdrawn per author request.

We demonstrate parabolic single-crystal diamond compound refractive lenses [1] designed for coherent x-ray imaging resilient to extreme thermal and radiation loading expected from next generation light sources. To ensure the preservation of coherence and resilience, the lenses are manufactured from the highest-quality single-crystalline synthetic diamond material grown by a high-pressure high-temperature technique. Picosecond laser milling is applied to machine lenses to parabolic shapes with a ~1-micron precision and surface roughness. A compound refractive lens comprised of six lenses with a radius of curvature R=200 microns at the vertex of the parabola and a geometrical aperture A=900 microns focuses 10~keV x-ray photons from an undulator source at the Advanced Photon Source facility to a focal spot size of ~ 10x40 microns^2 with a gain factor of ~100.\\ [1] S. Terentyev, V. Blank, S. Polyakov, S. Zholudev, A. Snigirev, M. Polikarpov, T. Kolodziej, J. Qian, H. Zhou, and Yu. Shvyd'ko Applied Physics Letters 107, 111108 (2015); doi: 10.1063/1.4931357

Due to the weak interaction of X-rays with matter and their small wavelength on the atomic scale, stringent requirements are put on X-ray optics manufacturing and metrology. As a result, these optics often suffer from aberrations. Until now, X-ray optics were mainly characterized by their focal spot size and efficiency. How- ever, both measures provide only insufficient information about optics quality. Here, we present a quantitative analysis of residual aberrations in current beryllium compound refractive lenses using ptychography followed by a determination of the wavefront error and subsequent Zernike polynomial decomposition. Known from visible light optics, we show that these measures can provide an adequate tool to determine and compare the quality of various X-ray optics.

Femto-second laser processing of polycrystalline CVD diamond was applied to manufacturing of X-ray planar refractive lenses. Surface morphology and material quality were analyzed with optical and scanning electron microscopy and X-ray radiography. Lenses were tested in a focusing mode at the III^rd generation synchrotron radiation source (ESRF).

Two dimensional compound refractive lenses (CRL) made out of single crystal diamond had been recently demonstrated [1, 2]. The use of compound refractive lens is inevitably associated with high x-ray absorption. One of the benefits of diamond as a material for CRL is its ability to withstand high instantaneous and average heat load. We used finite element method to simulate thermal effects in the lens. A steady state simulation is done for high average heat load conditions of ultimate storage rings. A time domain simulation is used for high peak power XFEL case. We compare diamond with beryllium, a common material for the CRL, and find that diamond temperature rise is less even though its x-ray absorption is higher.

Brilliant beams of hard x-rays, with geometrical cross-sections below 50×50 nm², are a standard research tool for synchrotron users. With the advent of lower emittance sources, such as NSLSII, Petra III and Max IV, and planned upgraded lattices, such as APS-2, SPING8-II, ESRF II and DLS II, nanofocusing optics operating in transmission mode will become more competitive than they are currently. In general, they suffer from lower efficiency than reflective optics, however they often have easier set-up and alignment, combined with a smaller footprint. Fabrication and exploitation of ultra-short focal refractive lenses has not witnessed the same progress in the last decade as other optics, such as multilayer mirrors and multilayer Laue lenses. This paper reports on current status of high-resolution lithography for fabricating silicon lenses and on proposed designs for a new class of refractive lenses with zero aberrations and good efficiency. The new designs are created with geometrical parameters matching the spatial resolution achieved by modern lithography and silicon etch technology.

Numerous atomic and molecular transitions that provide important diagnostics for astrophysical research exist in the Lyman-ultraviolet (LUV; 91.2 - 121.6 nm) and far-ultraviolet (FUV; 121.6 - 200 nm) bandpasses. Future astronomy and planetary science missions require the development of mirror coatings with improved reflectance between 90 - 200 nm which maintain optical performance in visible and IR wavelengths (320 - 2000 nm). Towards this end, we have developed an atomic layer deposition (ALD) process for optical coatings to enhance the efficiency of future space observatories. We measured the reflectance from 115-826 nm of sample optics, consisting of silicon wafers coated with lithium fluoride films deposited via ALD. We also measured the reflectance of sample optics stored in various environments, and characterized the effect of storage environment on visible and UV optical performance over week-long time scales. Minimal change in optical performance was observed for wavelengths between 200 and 800 nm, regardless of storage environment.

This paper describes the preliminary analysis and design of a water-cooled multilayer monochromator (MLM) system for the Illinois Institute of Technology’s BioCAT beamline at Argonne National Laboratory. The first substrate is designed to handle the heat load of an undulator beam with low tangential slope errors. The substrates will each have two multilayer coating strips to provide high flux 12 keV beams with either 0.5% or 1% spectral bandwidth. The new multilayer system which will be added to the beamline is expected to provide an increased photon flux of 50 to 100 times compared with the existing double crystal monochromator system and thus enhance beamline throughput and performance for applications where higher bandwidth is acceptable.

In the field of target diagnostics for Initial Confinement Fusion experiment, high resolution X-ray imaging system is seriously necessary to record the evolution details of target ablation-front disturbance at different energy points of backlight conditions. Kirkpatrick-Baez mirror is a wide used imaging system to achieve a large efficient field of view with high spatial resolution and energy transmitting capability. In this paper, we designed a novel type of reflective microscope based on Kirkpatrick-Baez structure, and this system can achieve 5μm spatial resolution at 600μm field of view specific energy point in one dimension.