BL 07.2 - ALOISA

Advanced Line for Overlayer, Interface and Surface Analysis (ALOISA)

ALOISA is a multipurpose beamline dedicated to the chemical and structural characterization of surfaces, adsorbates and thin films in UHV conditions. ALOISA offers the possibility to perform in-situ photoemission and absorption spectroscopy in a photon energy range of 130-1500 eV, when the storage ring is operated at 2.0 GeV (minimum photon energy of 150 eV, when operated at 2.4 GeV). The end-station is equipped with a homemade hemispherical electron spectrometer mounted on rotating frames for performing photoelectron diffraction measurements. A dedicated channeltron is used to perform NEXAFS measurements by partial electron yield to enhance surface sensitivity. The six degrees-of-freedom manipulator is mounted coaxially to the photon beam in order to keep the sample at grazing incidence, while the oreination of the surface with respect to the linear polarization of the beam can be changed from p to s without changing the incidence angle. This non conventional scattering geometry together with a high level of automation and a dedicated software make Aloisa specially suitable to perform polarization dependent NEXAFS measurements and resonant photoelectron spectroscopy/diffraction.

Beamline Resolving Power
5 * 103 [deltaE/E] @ 250 [eV]
5 * 103 [deltaE/E] @ 400 [eV]
5 * 103 [deltaE/E] @ 900 [eV]
Beamline Energy Range
129.13 - 1500 [eV]
Max Flux On Sample
1 * 1012 [ph/s] @ 400 [eV]
Spot Size On Sample Hor
150 - 200 [um]
Spot Size On Sample Vert
30 - 150 [um]
Photon Sources


Available Polarization
Linear horizontal
Deflection Parameter K
Energy Range
130 - 1500 [eV]
Number Of Periods
7 [cm]

Monochromator 1

Energy Range
130 - 1500 [eV]
Plane Mirror + Plane Grid
Resolving Power
5000 [E/deltaE] @ 400 [eV]
5000 [E/deltaE] @ 530 [eV]
Number Of Gratings
Grating Type
gold coated plane mirror 1200 lines/mm
Pre-focusing Mirror Type
Paraboloidal in sagittal focusing and grazing incidence (0.5˚)
Refocusing Mirror Type
Paraboloidal in sagittal focusing and grazing incidence (0.5˚)
Endstations or Setup

Endstation 1

Base Pressure
2 * 10-10 [mbar]


Sample Type
Other Sample Type
Solid polycrystalline, conductive
Mounting Type
Clips mounted on sample holder equipped with heater and thermocouple
Required Sample Size
X = 4 [mm], Y = 4 [mm], Z = 1 [mm]

Techniques usage

Absorption / NEXAFS
Electronic structure of empty states at the ionization edge, i.e. mapping of unoccupied molecular orbitals.
Polarization dependent NEXAFS dichroism to measure the average molecular orientation with respect to the surface.
Photoelectron emission / Angular Resolved PES
Exploiting the orbital symmetry to enhance/suppress the photoemission intensity to study symmetry/angular related properties, such as molecular orbital orientation, charge transfer direction (also see resonant photoemission).
Photoelectron emission / Photoelectron diffraction
Surface structure determination with chemical sensitivity.
Photoelectron emission / XPS
Chemical chracterization of surfaces and adsorbates by measurement of core level shifts. Mapping of the valence band state at resonance of the ionization thresholds (in combination with NEXAFS) for chemical analysis of the valence band/occupied molecular orbitals. Resonant photoemission for study of charge transfer dynamics at the femtosecond timescal by core-hole-clock technique.

Manipulator or Sample stage

Positioning Precision
X = 20 [um], Y = 20 [um], Z = 20 [um]
Dr. Luca Floreano
Dr. Albano Cossaro
Dr. Alberto Verdini
Dr. Martina dell'Angela
Photoelectron emission
  • Angular Resolved PES
  • Photoelectron diffraction
  • XPS
  • Other - Chemistry
control/Data analysis
Control Software Type
  • Labview
Data Output Type
  • text file
Data Output Format
Softwares For Data Analysis
  • Wavemetrics IGOR