Ab initio calculation of Spin-Polarized Low-Energy Electron Diffraction Pattern for the systems Fe(001) and Fe(001)-p(1x1)-O

The construction of a multi-channel vector spin polarimeter requires the development of a new detector type, which works as a spin polarizing mirror with high reflectivity and asymmetry properties to guarantee for a high figure of merit. Technical realizations are found by spin polarized electron scattering from a surface at low energies. A very promising candidate for such a detector suitable material consists of an oxygen passivated iron surface, as for example a Fe(001)-p(1x1)-O surface. We investigate in detail the electronic structure of this adsorbate system and calculate the corresponding spin-polarized low-energy electron scattering. Our theoretical study is based on the fully relativistic SPRKKR-method in the framework of density functional theory. Furthermore, we use the local spin-density approximation in combination with dynamical mean field theory to determine the electronic structure of Fe(001)-p(1x1)-O and demonstrate that a significant impact of correlation effects occurs in the calculated figure of merit.