A5040493892- Advanced X-ray Imaging Techniques
- X-ray Spectroscopy and Fluorescence Analysis
- Crystallography and Radiation Phenomena
- Advanced Electron Microscopy Techniques and Applications
- Advancements in Photolithography Techniques
- Particle Accelerators and Free-Electron Lasers
- Electron and X-Ray Spectroscopy Techniques
- Advanced Surface Polishing Techniques
- Diamond and Carbon-based Materials Research
- Nuclear Physics and Applications
- Optical Coatings and Gratings
- X-ray Diffraction in Crystallography
- Adaptive optics and wavefront sensing
- Optical measurement and interference techniques
- Advanced X-ray and CT Imaging
- Medical Imaging Techniques and Applications
- Magnetic properties of thin films
- Surface Roughness and Optical Measurements
- Advanced Measurement and Metrology Techniques
- Atomic and Molecular Physics
- Enzyme Structure and Function
- Particle accelerators and beam dynamics
- High-pressure geophysics and materials
- Laser-induced spectroscopy and plasma
- Advanced Fiber Laser Technologies
Elettra-Sincrotrone Trieste S.C.p.A.
2009-2020
AREA Science Park
1997-2013
Vitenparken
2006
European Synchrotron Radiation Facility
1997-1998
Universität Hamburg
1983-1997
University of Trieste
1997
Lawrence Berkeley National Laboratory
1996
École Polytechnique Fédérale de Lausanne
1996
IBM Research - Almaden
1987-1991
Fritz Haber Institute of the Max Planck Society
1989-1990
Near-edge x-ray-absorption fine-structure studies of ${\mathrm{O}}_{2}$ chemisorbed on Ag(110) and Pt(111) surfaces near 100 K reveal different predissociation stages molecular oxygen. exhibits only a ${\ensuremath{\sigma}}^{\mathrm{*}}$ resonance resembles single-bonded peroxo species. The O-O bond is aligned parallel to the surface, along [11\ifmmode\bar\else\textasciimacron\fi{}0] azimuth, with length 1.47\ifmmode\pm\else\textpm\fi{}0.05 A\r{}. also lies down but less perturbed from gas...
The design of a versatile high-precision eight-axis ultrahigh-vacuum-compatible polarimeter is presented. This multipurpose instrument can be used as self-calibrating polarization detector for linearly and circularly polarized UV soft-x-ray light. It also the characterization reflection or transmission properties (reflectometer) polarizing phase-retarding (ellipsometer) any optical element. Mo/Si, Cr/C, Cr/Sc, Ni/Ti multilayers in this polarizers analyzers have been investigated...
The temperature-dependent microscopic structure of plasma-deposited a-C:H and magnetron-sputtered a-C films, in situ sputter cleaned by argon bombardment, has been investigated near-edge (NEXAFS) extended (EXAFS) x-ray-absorption fine-structure studies. We find that the two films becomes indistinguishable after sputtering with a loss hydrogen for sample. sputtered at 30 \ifmmode^\circ\else\textdegree\fi{}C is characterized first-neighbor C-C bond length 1.445(10) A\r{}. Upon annealing...
In this letter we present a hard x-ray phase contrast microscope based on the divergent and coherent beam exiting an waveguide. It uses lensless geometrical projection to magnify spatial variations in optical path length more than 700 times. Images of nylon fiber gold test pattern were obtained with resolution 0.14 μm one direction. Exposure times as short 0.1 s gave already visible contrast, opening way high resolution, real time studies.
Metrology requirements for optical components third-generation synchrotron sources are taxing the state of art in manufacturing technology. We have investigated a number error commercial figure measurement instrument, Long-Trace-Profiler II, and demonstrated that, with some simple modifications, we can significantly reduce effect improve accuracy reliability measurement. By keeping head stationary moving penta prism along translation stage, as original pencil-beam interferometer design von...
This report discusses the properties of a 13-keV submicrometer x-ray beam exiting from waveguide. Waveguides for this spectral regime can be constructed by enclosing low-absorbing material between highly absorbant metals. Best performance is found about 0.1 μm guiding layer thickness. Measurements photon size close to exit and intensity distribution far will presented. From these data one derives at which identical number being in range offers interesting perspectives microscopy experiments...
A hard x-ray waveguide capable of reducing a 13 keV monochromatic beam in one direction from 30 to only 0.1 μm has been characterized with synchrotron radiation. The guiding structure consisted carbon layer sandwiched between two Ni layers sputter-deposited onto float glass. exiting at the end guide was observed when resonance effect due formation standing waves total reflection region takes place. measured divergence (1.3 mrad) agrees expectations. efficiency (exiting photon flux/incident...
X-ray waveguides can compress an incident beam for microscopy applications above 8 keV photon energy to sizes smaller than 100 nm in one dimension, a range which is not routinely accessed with other x-ray optics (e.g., Fresnel zone plates). Beryllium, because of its low absorption, expected provide the highest intensity gain. Measured gains beryllium waveguide 74 thickness exceed values at 13 and 20 energy, improvement by order magnitude compared previously reported performances. The same...
The Super-ESCA beamline has been designed for high resolution core level spectroscopy of adsorbates on single crystal surfaces using soft x-ray synchrotron radiation. It receives the light from an 81 period undulator with 5.6 cm and 4.5 m length in storage ring ELETTRA. tunability this insertion device, at a electron energy 2.0 GeV connected modified SX700 monochromator allows performance experiments photon range 100–2000 eV. This is now operational first absorption spectra are presented...
The article describes the ESCA microscopy beamline dedicated to high spatial resolution quantitative and qualitative analysis on surfaces interfaces. scanning microscope is constructed work both in transmission photoemission within photon energy range from 200 1200 eV with a of ∼0.1 μm. A Fresnel zone plate demagnifies beam submicrometer dimensions 109–1010 photons/s focus spot. photodiode hemispherical electron analyzer are used as detectors for recording transmitted x-rays emitted...
Experimental data with unprecedented submicrometre resolution obtained in a phase-contrast radiography experiment magnifying configuration are presented. The term 'phase contrast' here indicates that the phase retardation of coherent light matter was utilized as contrast mechanism. and divergent beam exiting an X-ray waveguide used lensless to magnify spatial variations optical path length up several hundred times. defocused image nylon fibre measured 0.14 micro m at object. Sufficient found...
This paper reports a simplified and compact mechanical scheme designed for providing alternatively high flux or spectral resolution from monochromator the 2 - 14 keV X-ray range in stationary spot at sample. The example case treats bending magnet source Elettra storage ring. properties of continuously tunable monochromatic beam are adapted variety experimental techniques, which include also need to operate sample total reflection regime, i.e. angles grazing incidence smaller than critical...
Thin-film slab waveguides can confine incident X-ray beams in one direction guiding layers as thin 10 nm. Consequently they provide attractive beam dimensions for microscopy purposes. This report presents a simple model and analytical equations the transmission calculation, which results consistent with rigorous calculations based on recursion techniques. By using these waveguide be compared directly other objectives. Ideally filter spatially coherent content out of an radiation efficiency...
We have recorded the extended x-ray-absorption fine structure (EXAFS) above carbon K edge for diamond and highly oriented crystalline graphite using 250--800-eV synchrotron radiation. The spectra are used to test phase amplitude transferability of C-C EXAFS signal between two bonding forms carbon. find excellent phaseshift with errors in distances less than 0.01 A\r{}. Amplitude is worse but better 20%. Implications our results structural determinations bonds molecules solids discussed.
The concept of variation the angle deflection in a spherical grating monochromator allows to keep defocus aberration at zero while keeping entrance and exit slit distances fixed. This report presents optimization this for different applications which one would always like work with maximum resolving power photon flux fixed position. Three designs are presented medium resolution (E/ΔE = 3000) soft x-ray microscopy studies energy range 200–1200 eV 20–300 high-resolution spectroscopy (E/ΔE≳10...
We have produced a multilayer transmission filter with 100 periods of Cr/C to achieve significant phase retardation while maintaining good for photon energies just below the carbon K edge. This device was installed into polarimeter behind SX700/3 monochromator at Berlin synchrotron radiation laboratory, BESSY. The phase-retardation properties were observed as theoretically predicted. Agreement between experiment and calculation could be obtained by introduction rather small interface...
This report discusses the optimization strategy, theoretical background and first experimental data of a new refractive lens for focusing X-rays. In order to reduce absorption X-rays in this transmission lens, optically passive material was removed from necessarily concave shape highly regular pattern. The feature dimensions require production replication by deep X-ray lithography, which allows shaping only one dimension. Consequently such can focus direction only, so crossed pair is needed...
This report presents a modification of an SX700 plane grating monochromator, which can be made to work stigmatically by introducing entrance slit. It will then provide the highest possible photon density in exit slit with resolving powers that very high because it is not any longer source-size limited. Instead adjusted according settings. The deterioration power slope errors ellipsoid avoided orienting this mirror for sagittal focusing dispersion plane. In configuration instrument matched...
Future space missions will operate in increasingly hostile environments, such as those low-perihelion solar orbits and Jovian magnetosphere. This exploration involves the selection of optical materials components resistant to environmental agents. The conditions are reproduced on ground through use ion accelerators. effects He particles coming from wind impinging a gold thin film have been systematically investigated, considering absorbed doses compatible with duration European Space Agency...
(1999). The elettra circular polarization beamline and electromagnetic elliptical wiggler insertion device. Synchrotron Radiation News: Vol. 12, No. 4, pp. 34-38.