Advanced Line for Overlayer Interface and Surface Analysis

Contact persons: Luca Floreano, Albano Cossaro, Martina dell'Angela, Alberto Verdini

Last update 29/06/2018

ALOISA is a Synchrotron beamline dedicated to the study of the electronic and structural properties of surfaces, adsorbates and interfaces by means of photoemission and absorption spectroscopy. At the end of 2016, the original wiggler/undulator has been replaced with a new phase-undulator (designed by Elettra) delivering a photon beam in the 130-1500 eV range, with improved performances at the K-edge energy range of light elements (e.g. B, C, N, O, F).  The monochromator is equipped  with a plane grating-plane mirror dispersive system coupled to parabolidal mirrors (in and out) in sagittal focusing and grazing incidence (0.5˚), which yields high flux (>10^11 ph/sec) and resolution (R.P.>5000) in the 130-1000 eV range.

The UHV end-station is equipped with a combination of angle resolved electron  spectrometers to perform in-situ the electronic and structural characterization by means of XPS, PED, NEXAFS, RESPES and RESPED. The main electron analyzer (66 mm radius) is equpped with a 2D delay-line detector. The sample manipulator is mounted coaxially to the photon beam in a grazing incidence scattering geometry.  The non-conventional manipulator configuration together with the installation of the electron analyzer on rotating frames allows one to freely change the scattering geoemetry as a function of the surface orientation with respect to the linear polarization of the photon beam, the grazing angle and the emission angle.

ALOISA has an additional branch line that exploits the low energy range (150-900 eV) of the dispersive system and offers a flexible output for coupling to Users’ owned endstations. At present, the branch line is equipped in alternative: 

- with the HASPES experimental chamber made by a Helium Atom Scattering apparatus, equipped with a  custom-made 150mm electron analyzer with a 2D delay-line detector, for real time He diffraction and XPS; 

-with the ANCHOR experimental chamber (FIRB project, Rif. Albano Cossaro) that has been installed in  between the Exit Slits and the HASPES endstation. ANCHOR is equipped with a PSP 150mm electron analyzer (with an 2D delay-line detector) with a monochromatized Omicron X-ray source for in- and off-line XPS  and UPS. The chamber is connected also to a Yb:YAG laser synchronized with the Elettra Storage Ring (SUNDYN project - resp. Dr. Martina dell'Angela) in order to perform time resolved 2 Photon Photoemission and time-resolved X-ray spectroscopy experiments.

Part of the research activity is dedicated to the study of Surfaces, films and interfaces, in particular of Organic Interfaces and Charge Transfer.

Collaborators: prof. Alberto Morgante, prof. Dean Cvetko, Dr. Roberto Gotter, Dr. Gregor Kladnik, Dr. Gregor Bavdek

For more details, how to apply and the updated list of publications see ALOISA@Elettra