La/B 4 C multilayer mirrors with an additional wavelength suppression

In this paper, the authors report on La/B(4)C multilayer mirrors designed for an incidence angle of 45° with both maximum reflectivity at a wavelength of 6.7 nm and reflectivity suppression at a wavelength of 20.1 nm. These mirrors were deposited for the EIS-TIMER at the FERMI@Elettra Free Electron Laser. The multilayer structure and optical properties were characterized using grazing incidence X-ray reflectometry with Cu-K(α) radiation and EUV reflectometry in the spectral region of 6.5 - 21.0 nm. An anti-reflective coating designed at the wavelength of 20.1 nm had to be deposited on top of the high reflective La/B(4)C multilayer mirror optimized at a wavelength of 6.7 nm. Measured reflectivities of 53.4% at the wavelength of 6.72 nm and 0.15% at the wavelength of 20.1 nm were simultaneously achieved. It is shown that the reflectivity loss at the wavelength of 6.7 nm due to the utilization of antireflective coating designed at the wavelength of 20.1 nm can be minimized up to 1.0%

The COMIX polarimeter: a compact device for XUV polarization analysis

We report on the characterization of a novel extreme-ultraviolet polarimeter based on conical mirrors to simultaneously detect all the components of the electric field vector for extreme-ultraviolet radiation in the 45–90 eV energy range. The device has been characterized using a variable polarization source at the Elettra synchrotron, showing good performance in the ability to determine the radiation polarization. Furthermore, as a possible application of the device, Faraday spectroscopy and time-resolved experiments have been performed at the Fe M2,3-edge on an FeGd ferrimagnetic thin film using the FERMI free-electron laser source. The instrument is shown to be able to detect the small angular variation induced by an optical external stimulus on the polarization state of the light after interaction with magnetic thin film, making the device an appealing tool for magnetization dynamics research

Spiegel zur Reflexion von EUV-Strahlung mit Spannungskompensation und Verfahren zu dessen Herstellung

Es wird ein Spiegel (5) zur Reflexion von EUV-Strahlung angegeben, umfassend eine auf einem Substrat (1) angeordnete spannungskompensierende Schichtenfolge (2), die abwechselnde erste Schichten (2a) und zweite Schichten (2b) aufweist, wobei die ersten Schichten (2a) Bor, ein Bornitrid, ein Borcarbid oder ein Boroxid aufweisen und die zweiten Schichten (2b) Lanthan, ein Lanthannitrid, ein Lanthancarbid oder ein Lanthanoxid aufweisen, und wobei die spannungskompensierende Schichtenfolge (2) eine Zugspannung aufweist. Über der spannungskompensierenden Schichtenfolge (2) ist eine reflektierende Schichtenfolge (3) angeordnet, die abwechselnde dritte Schichten (3a) und vierte Schichten (3b) aufweist, wobei die reflektierende Schichtenfolge (3) eine Druckspannung aufweist. Weiterhin wird ein Verfahren zur Herstellung des EUV-Spiegels (5) beschrieben

Spiegel zur Reflexion von EUV-Strahlung in Strahlung im Spektralbereich zwischen 6 nm und 10 nm und optische Anordnung mit dem Spiegel

Es wird ein Spiegel (10) zur Reflexion von EUV-Strahlung im Spektralbereich zwischen 6 nm und 10 nm beschrieben, der mindestens eine auf einem Substrat (1) angeordnete oxidationshemmende Schicht (2) umfasst, die ein Lanthanoxid, ein Ceriumoxid, ein Thoriumoxid, ein Uranoxid oder diamantartigen Kohlenstoff aufweist. Weiterhin wird eine optische Anordnung (100) beschrieben, die eine EUV-Strahlungsquelle (11) und mindestens einem derartigen Spiegel (10) aufweist

Actinic damage of Y/Mo multilayer optics in a table-top plasma-driven x-ray laser

A Y/Mo multilayer coating, optimized for top reflectivity at ? \'01 12 nm, has been nano-inspected after long-term operation at the in-house soft x-ray laser. The surface and optical inspections were complemented by electron microscopy on cross sections, prepared with focused ion beam technology. A factor of 2.5 loss of reflectivity in the exposed area (ca. 30% relative loss every 100 shots), with concomitant nanoscale photodamage and particle fallout, was found. The x-ray-laser-induced damage extended as deep as 250 nm beneath the surface and as wide as the millimeter spot size

Optical reflector coatings for astronomical applications from EUV to IR

Optical coatings are an integral part of superior optical components. Astronomical applications (ground- and space-based) place especially high demands on these coatings, not only with regard to their optical performance but also to their mechanical and environmental stability, their thermal properties, and their radiation resistance. This article presents a short overview of several coating solutions developed in recent years at Fraunhofer IOF in order to meet the challenging demands of astronomical applications. The focus is placed on high reflective coatings for different wavelength regions including coatings for the VUV range below 100nm, coatings for the DUV wavelength range above 100nm and VIS/NIR/IR coatings. Further, amorphous silicon layers will be introduced which can be polished to very low roughness values and therefore can act as polishing layer for the manufacture of ultraprecise optical components from metal substrates

Towards attosecond imaging at the nanoscale using broadband holography-assisted coherent imaging in the extreme ultraviolet

In recent years nanoscale coherent imaging has emerged as an indispensable imaging modality allowing to surpass the resolution limit given by classical imaging optics. At the same time, attosecond science has experienced enormous progress and has revealed the ultrafast dynamics in atoms, molecules, and complex materials. Combining attosecond temporal resolution of pump-probe experiments with nanometer spatial resolution would allow studying ultrafast dynamics on the smallest spatio-temporal scales but has not been demonstrated yet. Unfortunately, the large bandwidth of attosecond pulses usually hinders high-resolution coherent imaging. Here we present a robust holography-enhanced coherent imaging method, which allows combining high quality and high spatial resolution coherent imaging with a large spectral bandwidth. By implementing our method at a high harmonic source we demonstrate, for the first time, a spatial resolution of 34 nm (2.5 {\lambda}) in combination with a spectral bandwidth supporting a Fourier limited pulse duration of only 380 as. The method is single-shot capable, additionally retrieves the spectrum from the measured diffraction pattern, and is thus immune against shot-to-shot fluctuations. This paves the way for an ultrafast view on nanoscale dynamics e.g. ultrafast charge transfer or ultrafast spin currents being relevant for Petahertz electronics and future data storage