Novel hybrid reflection zone plates as dispersive elements will allow time-resolved Near Edge X-ray Absorption Fine Structure (tr-NEXAFS) studies in a wide photon energy range from 100 – 1500 eV. We describe two tr-NEXAFS setups using a laser produced plasma (LPP) as well as a high harmonics generation (HHG) source.
We present first experimental results on wavelength-dispersive soft X-ray spectroscopy of TiO2 in the vicinity of the Ti Lσ fluorescence line with a central energy of about 452.2 eV, demonstrating the functionality of a newly developed, laboratory-scaled setup. In our instrument, the micron-sized photon emission from an electronexcited source is collected efficiently by a rotationally symmetric, ellipsoidal mirror and subsequently dispersed by a reflection zone plate with inscribed diffractive wavefront correction, to compensate for figure and alignment errors of the ellipsoid to some degree. The measured data, recorded with a CCD camera in one meter from the source, show clearly separated peaks from different Ti L (398.3 eV and 452.2 eV) contributions and O Kα emission (523.1 eV) with an energy resolving power around 38 and a signal-to-noise ratio between 4.4 and 10.7.
SIOS Meβtechnik GmbH developed a universal interferometrical profilometer for 3D measurements of freeform optics topography. Due to the measurement principle using a scanning differential interferometer, no expensive and individually shaped reference optics are required. All optic shapes such as plane-,spherical-, and freeform-optics with local slopes up to 7 mrad and sizes up to 100 × 100 mm2 can be measured with sub-nanometer resolution. The capability of the setup has been proven by measurements of highly precise machined silicon mirrors (plane and spherical). A maximum of ± 3 nm peak-valley deviation between two subsequent measurements of a 30 mm × 100 mm plane mirror topography has been achieved, which proves a very good repeatability. Furthermore, measurement results show very good accordance with those from Fizeau interferometer measurements of this precision plane mirror. The maximum deviation was ± 10 nm, which is a hint to a very good accuracy of our measurements. Furthermore, form parameters such as the radii of spherical mirrors can be determined precisely due to the interferometer-based synchronous measurements of the x- and y- positions of the z- topography. A reproducibility of 1.4 × 10-4 of the radius measurements of a 29 m radius mirror was achieved, whereat the mirror was measured on different supports and in different orientations.
In 2019, the Institut für angewandte Photonik (IAP) e. V. in cooperation with Nano Optics Berlin (NOB) GmbH and SIOS Meßtechnik GmbH has made an important progress in the technology for precision soft X-ray optics – the development of three-dimensional (3-D) reflection zone plates (RZPs) with diffractive compensation of slope errors. 2-D mapping of spherical and toroidal grating substrates was used for the metrology of their individual profile. Based on these data, the inscribed grating structure, which corrects the slope error distribution, was computed. The correction algorithm has been implemented as a Python script, and first pilot samples of slope error compensated RZPs are in fabrication process. The 3-D device can replace two or three components in an optical scheme and, therefore, reduce absorption losses by several orders of magnitude. Beyond, the fabrication of customized 3-D Fresnel structures on curved substrates promises considerable improvements for efficiency, resolution and energy range in wavelength dispersive applications. As an example, we present simulations for a compact instrument within (150 – 250) eV. Further development of this approach toward commercial availability will enable the design and construction of compact soft Xray monochromators and spectrometers with unique parameters.
In most cases, neutron optical elements like polarisers or collimators use coated surfaces which define the neutron flight path in air or vacuum. To reduce the size of such elements silicon single crystals can be used as the medium in which the neutrons travel. We have built and tested a neutron polarising bender which consists of a stack of thin silicon wafers. The neutrons enter at the front side. Inside the wafers the spin up component is reflected from the supermirror coated side and can leave the wafers while the spin down component passes the supermirror and is absorbed in the Gd layer of the adjacent wafer. Other neutron optical element, we tested for the first time are several collimators made from silicon wafers coated with either Gd or reflecting coatings below an absorbing Gd layer. These collimators produce a beam with quasi-rectangular distribution of angles, which represents an intensity gain at equal resolution compared to the triangular distribution in conventional Soller collimators. Finally, we report on the first test of a solid state radial collimator. Some general aspects of sold state neutron optical elements are also discussed.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.