x-ray spectroscopy with selectable polarization, x-ray magnetic linear/circular dichroism, time-resolved phenomena, out-of-equilibrium phenomena (pump-probe)

Elettra synchrotron, Apple II undulators; variable polarization (horizontal, vertical, circular ±); beam size on the sample 350X350 (HxV, µm2); Vertical size can be reduced on request, flux on sample @ 1 µm slits (best resolution) (ph./s) 2x1012-6x1010

35-1650 eV

Hamamatsu fast fluorescence detector; photodiode, setup for x-ray absorption transmission measurement, drain current for total electron yield, Scienta R3000 analyzer for partial electron and Auger yield; setup for measurements in static liquid environment

(E/dE) 20000-5000

Many samples can be accommodated in a 25x25mm2 area; T range: 50-1200 K (PID-controlled)

Base pressure: UHV

Heating stages (ebeam, direct current, PBN), ion gun (VG), 4 evaporator ports (CF40), gas inlet valve (variable leak valve), diamond file scraper, cleaver, LEED (OciLEED); evaporators for organic molecules; e-beam evaporator (Omicron) for metals (evaporation at low sample temperatures is also possible)

ARPES and XPS are possible in the same chamber; 4 degree-of-freedom manipulator. x-ray magnetic circular dichroism (max 0.5 T, measurements in remanence); possibility to apply electric fields (measurements in remanence); possibility to superimpose synchrotron beam to laser beam for pump-probe measurements (100 ps resolution)

XCMD, XLMD (X-ray linear magnetic dichroism), LMDAD (linear magnetic dichroism in the angular distribution)

Elettra synchrotron, Apple II undulator; variable polarization (horizontal, vertical, circular ±); beam size on sample 500x200 (HxV, µm2), entry slit reduction to 100x100 possible, zone plate optical condenser reduction to 1x3 possible

150-1600 eV

Omicron EA 125 analyser; drain current Keithley 6514 picoammeter (for XAS/XMCD/XMLD); 10x10 mm2 silicon photodiode; total yield 20mm channeltron

(E/dE) 5000

T range: 30K- 300K (He flow cryostat) for LT stage (while measuring), 300K-700K for HT stage (while measuring); magnetic field: up to 1000 Oe in pulse mode, up to 200 Oe in continuous mode

Preparation chamber with: 3 heating stages HT (RT- 2000K), WT (170K - 900K), LT (RT - 700K), ion gun (SPECS IQE11/35), 3 evaporator ports (CF40), gas inlet valve (variable leak valve), LEED+AES (Omicron SPECTALEED)

MOKE magnetometry: transversal (Hmax=600 Oe), polar (Hmax=3000 Oe), 3D (Hmax=80 Oe); atomic resolution STM (room temperature, ETH-Z built)

The X-Treme beamline is dedicated to x-ray magnetic (circular or linear) dichroism technique in the soft x-ray range. The technique is element selective and is used for example for the study of magnetic anisotropy and exchange coupling. The energy range covers the L2,3-edges (2p to 3d transition) of 3d transition metals and M4,5-edges of lanthanides (3d to 4f transition), in addition to the K-edges of light elements like O, N, F. Scientific areas of interest are: single molecule magnets, magnetic nanocrystals, self-assembly of nanomagnets on surfaces and strongly correlated electron systems

Elliptical polarizing undulator, linear (0 to 90o) or circular (left/right), flux (700eV): 4x1015 photons/s/0.1%BW/0.4 A, focused spot size: exit slit µm x 230 µm (V x H)

400 - 2000 eV

Total electron yield (TEY); if requested, total fluorescence yield (TFY) or transmission can be acquired in parallel with TEY

>5000

Sample temperature: 2K-370K, max B-field along beam direction: 7 T, max B-field vectorial form: 2T

Load-lock, in-situ sample preparation, heating cooling stage (20-1500K), Omicron variable temperature STM, metal evaporator (Omicron Triple EFM), molecular evaporator (Kentax TCE-BSC 3cell with double power supply), Auger spectrometer, sputter gun, quartz balance

Time resolution<50ps

The soft x-ray analytics facility WERA provides a coherent combination of electron spectroscopies and microscopies for studying in detail the chemical (electronic) and magnetic structure of bulk materials, thin films, and micro- and nanostructured objects. Methods for Electron spectroscopy and spectromicroscopy: XAS, PES (XPS), SXMCD, µ-XAS, µ-PES (±-XAS), µ-SXMCD, topography Equipment: Three experimental stations at WERA equipped with PEEM, electron energy analyzer, detectors, cryostats, sample preparation chambers, loadlocks, in-vacuo sample transfer etc.