IXXS-spectrometer at the XRD1-beamline: Improvements and new results

TIRAO, G.; C. CUSATIS; G. STUTZ

Campinas, Brasil

Congreso; XI Reunion Anual de Usuarios del LNLS; 2001

Inelastic x-ray scattering spectroscopy (IXSS) is a technique to investigate eV electronic excitation in condensed matter systems1, which has been increasingly used in the last decade. The development of new synchrotron radiation-based x-ray spectrometers has it made possible to carry out experiments of inelastic scattering both with higher energy resolution and signal-to-background ratio than those obtained from conventional x-ray sources. These improvements of the experimental conditions along with the energy tunability of a synchrotron beam have demonstrated the large potential of synchrotron sources in the field of inelastic x-ray scattering. During 1999 an IXSS-spectrometer consisting basically of a sagitally focusing double crystal monochromator and of a spherically focusing analyser crystal was mounted at the XRD-beamline of the LNLS2. An overall energy resolution close to 1 eV and an acceptable signal-to-noise ratio could be achieved. This allowed us to obtain the first spectra of inelastic scattering of x-rays by plasmon excitation in Be at LNLS2, showing the feasibility to make IXSS-experiments at this synchrotron source. Some modifications in the setup were introduced during the year 2000 in order to improve the focusing properties of the analyser and therefore to match the size of the focused beam to the active area of the detector.