Band structure spin resolved

Information on the spin resolved band structure of ferromagnetic materials can directly be obtained from spin resolving photoelectron spectroscopy. Using polarized radiation spin integrating photoemission techniques already enable to have access to magnetic properties. An enhancement of the surface sensitivity can be achieved using neutral excited spin polarized atoms which move towards the sample and are de-excited by tunneling electrons from the surface with a subsequent emission of electrons. 

With increasing film thickness the electronic structure of the adsorbate overlayer becomes undistinguishable to that of the bulk material this will be demonstrated for Fe evaporated on W(llO) [13]. In the following it will be shown that a thickness of 20 layers is already sufficient to map the transitions in the spin resolved bulk band structure of Fe(llO). The analogous behavior was found for Co(OOOl) films on W(llO) [14]. 

Fig. 5.4 Spin resolved band structure for bcc-Fe along the Z direction (adapted from [24]). Majority bands are shown as solid lines, minority bands as broken lines. The arrows represent the direct transitions corresponding to the experimentally observed structures in the majority (filled circle) and minority (open circle) spin channel (cf. Fig. 5.3) (from [13], used with permission)...

Magnetic samples are exposed to ultraviolet radiation and the energies and spin orientation of the emitted photoelectrons are measured to reveal information about the spin resolved valence band electronic structure of the material. Range of operation typically 10—200 eV. This technique is similar to ultraviolet photoelectron spectroscopy but SPUPS is also sensitive to the polarisation of the electrons as well as their energy. 

Spin resolved valence band and shallow core level electronic structure of the top few atomic layers. 

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