SPIN REVERSAL AND CIRCULAR-DICHROISM IN VALENCE-BAND PHOTOEMISSION FROM 3D-FERROMAGNETS

The influence of spin-orbit coupling on valence-band photoemission from 3d-ferromagnets is explored by analytical evaluation of dipole matrix elements and by numerical calculations using a fully relativistic ''one-step model'' formalism. For the prototype case of normal emission from ferromagnetic Ni(001) with magnetization normal to the surface, spin-resolved spectra produced by normally incident linearly and circularly polarized light reflect not only the majority and minority spins of initial states but also exhibit sizeable features of reversed spin polarization. The spin-averaged spectra due to circularly polarized light show a strong asymmetry upon reversal of the magnetization, i.e. magnetic circular dichroism.