SPECS 2D-CCD, User Manual

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Manual V2.docx | Status 10.12.2015 | Version 1
5.2.1 Retardation stage
Following the 90° deflector, the electron beam passes a retardation stage consisting of the
lens tubes L4C (on the same potential as L4B), L5B, L4D and L4E. L4E is the entrance of the
Ferrum detector. The electrons enter the spin Ferrum detector with a fixed kinetic energy of
50 eV.
3D spin polarization detection 5.3
The Ferrum detector will detect electrons with spin polarization along its two main axes of
detection, see the Focus Ferrum Spin Detector Manual. The detection axis is selected by
selecting coil 1 or 2 when magnetizing the scattering target. If the Ferrum detector is
oriented as shown in Figure 13, this means that by magnetizing with coil 1, it will detect the
spin polarization component normal to the sample surface. This is independent of the
setting of the rotator lens, since the rotator lens does not affect the spin component along
the rotator lens axis.
By magnetization with coil 2, one of two components parallel to the sample surface is
detected, depending on the setting of the rotator lens. Note, however, that due to the action
of the rotator lens, the two main axis of detection parallel to the sample surface will be at an
angle of 45° to the energy dispersion plane of the PHOIBOS analyzer (the plane of the paper
in Figure 13). The main detection axes and the corresponding settings are summarized in
Figure 15.