Magnetic circular dichroism in 5p photoemission from Gd and Tb metal

The isotropic and magnetic-circular-dichroism (MCD) 5p core-level photoemission (PE) spectra of Gd(0001) and Tb(0001) are presented. Large MCD effects were observed at the low-binding-energy side, gradually reducing in amplitude at higher binding energies. Both the isotropic and the MCD-PE spectra can be well reproduced by a many-particle intermediate-coupling approach taking spin-orbit, Coulomb, and exchange interactions properly into account. We also present a simple model to understand the global line shape of the MCD spectra. The MCD permits an accurate determination of the values of the Coulomb and exchange interactions in the final state.