MONOCRHOMATIZED VUV SOURCE
Ultimate UPS, ARPES, PEEM & µ-ARPES
- Dispersive element with 20 % transmission for He I and II
- Photon flux He I: > 1x 1012 Photons/s/mm² He II:> 2x 1011 Photons/s/mm²
- Spot size < 300 µm (ø 1.7mm light capillary)
- Working distance 6.5 cm
- Ease of operation
- Operating pressure down to 10-10 mbar range (with 3rd pumping stage)
Photo electron spectra of
W (100) using FOCUS CSA
Top: Satellites
He I-β and γ present
Bottom: No satellites
Momentum microscopy of Ag (111) using FOCUS IEF-PEEM
Without
Monochromator
With
Monochromator
Top: Shadow-structure
visible due to He I-β
Bottom: Band-structure
due to He I-α solely
| Photo current He I | > 40 nA (photo current with VUV-Diode) |
| Photo current He II | > 12 nA (photo current with VUV-Diode) |
| Useful gas discharge lines: | He I, He II |
| Spot diameter: | < 300 µm (1.7mm capillary) |
| Photon line width: | < 2 meV (He I radiation) |
| Source alignment: | CF 63 port aligner |
| Pumping: | 2- or 3-stage differential pumping |
| Working distance: | Ca. 70 mm (clearance to measurement position) |
| Mounting flange: | DN 63 CF or larger |
| Insertion depth: | Customized (to be defined) |
| Adjustment dispersive element: | Rotary drive and z-shift |
| Cooling: | Water cooling |
| Bake out temperature: | 150°C |
| Plasma ignition: | automatic |
| Capillary (mm) : | 0.8 / 1.2 / 1.7 (standard) / 2.2 |
The VUV source power supply is a fully digital unit with integrated pressure measurement and automated plasma ignition. It delivers up to 1 kV anode voltage, up to 300 mA discharge current and a very stable discharge regulation.
geometry
