The CASSIOPEE beamline is a soft X-ray beamline dedicated to high resolution ARPES, spin-resolved photoemission and resonant spectroscopies in the 8 eV-1500 eV photon energy range. This wide energy range allows both surface and bulk studies of condensed matter. The beamline uses two undulators as a source with high flux and adjustable polarisation. The energy is selected by a high resolution PGM (Plane Grating Monochromator) with VLS (Variable Line Spacing) and VGD (Variable Groove Depth) gratings for best efficiency and spectral purity of the light. After the monochromator, the beamline is divided into two branches, supplying photons to two end stations (Spin-resolved Photoemission, and High Resolution Angle-resolved Photoemission), both connected to a Molecular Beam Epitaxy chamber for sample growth and caracterisation.

Beamline Energy Resolution
6 * 10-3 [eV] @ 20 [eV]
Beamline Resolving Power
3 * 10-4 [deltaE/E] @ 20 [eV]
Beamline Energy Range
8 - 1500 [eV]
Max Flux On Sample
5.5 * 1010 [ph/s] @ 50 [eV]
Spot Size On Sample Hor
50 - 75 [um]
Spot Size On Sample Vert
25 - 50 [um]
Angle Of Incidence Light On Sample Value
0 - 90 [degrees]
Photon Sources

HU256

Type
Undulator
Available Polarization
Circular
Variable Polarization
Yes
Energy Range
8 - 150 [eV]
Number Of Periods
14
Period
256 [mm]

HU60

Type
Undulator
Available Polarization
Linear horizontal, Linear vertical, Circular
Variable Polarization
Yes
Energy Range
100 - 1500 [eV]
Number Of Periods
30
Period
60 [mm]
Monochromators

Monochromator

Type
SX700 monochromator
Endstations or Setup

ARPES

Description
6-axis manipulator
Temperature from 13 to 300K
Spectrometer
Scienta R4000
Base Pressure
1 * 1010 [mbar]
Endstation Operative
Yes

Sample

Sample Type
Crystal
Mounting Type
Omicron plate

Manipulator or Sample stage

Description
In-house developped cryogenic sample holder. Temperature from 13 to 300 K
Degrees Of Freedom
6
Translator Stages
3
Cradles
3
Positioning Precision
X = 0.01 [mm], Y = 0.01 [mm], Z = 0.01 [mm]
Range Of Movement
X = 8 [mm], Y = 8 [mm], Z = 10 [mm]

MBE

Description
The CASSIOPEE MBE chamber is equipped for surface science: Ion gun, LEED, RHEED, Auger Spectroscopy and 3 sample stages:
1. Electron bombardment heating and phi rotation for RHEED measurement
2. Liquid N2 cooling
3. Direct current heating
Base Pressure
1 * 1010 [mbar]
Endstation Operative
Yes

Sample

Sample Type
Liquid

Manipulator or Sample stage

Degrees Of Freedom
5
Translator Stages
3
Cradles
3

Spin-resolved photoemission

Description
The Spin-Resolved Photoemission experiment is equipped with a Scienta SES2002 electron analyzer, which has been modified by the Scienta company to incorporate a Mott detector for spin analysis (see Figure 2). Part of the electron beam is sent towards the usual Scienta 2D detector, while the rest goes towards the Mott detector through transfer optics. The analyzer is mounted with horizontal slits. Angular resolution is then achieved in the horizontal direction. To accept the Mott detector, the 2D detector has been reduced to 1”, thus reducing the angular acceptance of the analyzer to ±8°.
Spectrometer
Scienta SES-2002
Base Pressure
1 * 1010 [mbar]

Sample

Sample Type
Crystal
Mounting Type
Omicron plate

Manipulator or Sample stage

Degrees Of Freedom
3
Translator Stages
3
Cradles
1
Techniques
Photoelectron emission
  • Angular Resolved PES
  • Spin-resolved ARPES
  • UPS
  • XPS
Disciplines
Physics
  • Hard condensed matter - electronic properties
  • Hard condensed matter - structures
  • Surfaces, interfaces and thin films
control/Data analysis
Control Software Type
  • Igor pro
Data Output Type
  • spectra or images
Data Output Format
  • ascii or Igor pro packed experiments
Softwares For Data Analysis
  • Igor pro
Equipment That Can Be Brought By The User
Vacuum suitcase
Evaporators
Other Equipment Available On Site
Vacuum suitcase, Evaporators, RHEED, LEED, Auger, Ion gun
in partnership with