K- and spin-dependent hybridization effects in Ce monolayer

Abstract

Here we present applications of the periodic Anderson model (PAM) to consideration of wave vector (k)- and spin-dependent hybridization effects in Ce metal. It was shown that k-dependent splitting of the 4f ionization peak of Ce/W(1 10) are correctly described in the framework of the PAM (Coulomb repulsion between two f electrons localized on the same lattice site Uff→∞). Our results show that the wave vector is conserved upon hybridization. In case of the magnetically ordered Ce monolayer, spin- and angle-resolved resonant photoemission spectra reveal spin-dependent changes of the Fermi-level peak intensities (which reflect the hybridization strength). That indicate a spin-dependence of 4f hybridization and, thus, of 4f occupancy and local moment. The phenomenon was also described in the framework of PAM by 4f electron hopping into the exchange split Fe 3d derived bands that form a spin-gap at the Fermi energy around the T point of the surface Brillouin zone.