In: Nuclear Instruments and Methods in Physics Research B: Beam Interactions with Materials and Atoms, 2005, vol. 238, p. 353
High-resolution measurements of the resonant X-ray Raman scattering (RRS) of Al and Si and their oxides were performed at the European Synchrotron Radiation Facility (ESRF) in Grenoble, France, using a von Hamos Bragg-type curved crystal spectrometer. To probe the influence of chemical effects on the RRS X-ray spectra, Al₂O₃ and SiO₂ samples were also investigated. The X-ray RRS spectra...
|
In: Review of Scientific Instruments, 2012, vol. 83, no. 10, p. 103105
We report on the design and performance of a wavelength-dispersive type spectrometer based on the von Hamos geometry. The spectrometer is equipped with a segmented-type crystal for x-ray diffraction and provides an energy resolution in the order of 0.25 eV and 1 eV over an energy range of 8000 eV–9600 eV. The use of a segmented crystal results in a simple and straightforward crystal...
|
In: Journal of Synchrotron Radiation, 2010, vol. 17, no. 3, p. 400-408
The development of a wavelength-dispersive spectrometer for microfluorescence analysis at the X-ray Microscopy ID21 beamline of the European Synchrotron Radiation Facility (ESRF) is reported. The spectrometer is based on a polycapillary optic for X-ray fluorescence collection and is operated in a flat-crystal geometry. The design considerations as well as operation characteristics of the...
|
In: Review of Scientific Instruments, 2007, vol. 78, no. 9, p. 093102
High-resolution x-ray measurements were performed with a von Hamos-type bent crystal spectrometer using for the detection of the diffracted photons either a back- illuminated charge-coupled device (CCD) camera or a front-illuminated one. For each CCD the main x-ray emission lines (e.g., Kα, Kβ, Lα, and Lβ) of a variety of elements were measured in order to probe...
|
Thèse de doctorat : Université de Fribourg, 2007 ; no 1568.
|
In: Physical Review Letters, 2006, vol. 97, p. 073001
We report on the first high-resolution measurements of the K x-ray resonant Raman scattering (RRS) in Si. The measured x-ray RRS spectra, interpreted using the Kramers-Heisenberg approach, revealed spectral features corresponding to electronic excitations to the conduction and valence bands in silicon. The total cross sections for the x-ray RRS at the 1s absorption edge and the ...
|
In: Scientific Reports, 2016, vol. 6, p. 33292
X-ray techniques have evolved over decades to become highly refined tools for a broad range of investigations. Importantly, these approaches rely on X-ray measurements that depend linearly on the number of incident X-ray photons. The advent of X-ray free electron lasers (XFELs) is opening the ability to reach extremely high photon numbers within ultrashort X-ray pulse durations and is leading...
|
In: Structural Dynamics, 2014, vol. 1, no. 2, p. 021101
Physical, biological, and chemical transformations are initiated by changes in the electronic configuration of the species involved. These electronic changes occur on the timescales of attoseconds (10−18 s) to femtoseconds (10−15 s) and drive all subsequent electronic reorganization as the system moves to a new equilibrium or quasi-equilibrium state. The ability to detect the dynamics of...
|
In: The Journal of Physical Chemistry Letters, 2014, vol. 5, no. 1, p. 80–84
Chemical reactions are always associated with electronic structure changes of the involved chemical species. Determining the electronic configuration of an atom allows probing its chemical state and gives understanding of the reaction pathways. However, often the reactions are too complex and too fast to be measured at in situ conditions due to slow and/or insensitive experimental techniques. A...
|
In: Journal of Applied Physics, 2009, vol. 105, p. 086101
We report on the application of synchrotron radiation based high-resolution grazing-emission x-ray fluorescence (GEXRF) method to measure low-level impurities on silicon wafers. The presented high-resolution GEXRF technique leads to direct detection limits of about 10¹² atoms/cm². The latter can be presumably further improved down to 10⁷ atoms/cm² by combining the synchrotron...
|
