MAGNETIC-X-RAY CIRCULAR-DICHROISM IN PHOTOELECTRON-SPECTROSCOPY AND DIFFRACTION

In this paper, we discuss a series of photoelectron-spectroscopy (PS) and photoelectron-diffraction (PD) studies utilizing magnetic x-ray ci rcular dichroism and fully spin-specific, multiple-scattering calculat ions for analysis of the experimental results. The test system used wa s perpendicularly magnetized, ferromagnetic monolayer Fe/Cu(001), prep ared and probed at low temperature. Two sets of states were used: the Fe2p at binding energies of over 700 eV (large spin-orbit and small ex change splittings) and the Fe3p at a binding energy of near 53 eV (spi n-orbit and exchange splittings approximately equal). The PS and PD me asurements made were angularly resolving and compared to calculational results which were similarly angularly dependent. Both ''exchange shi fts'' and intensity variations of spectral structure were observed. Th e impact of ''j-state mixing'' was seen in both the Fe2p and 3p spectr a. Our results indicate a ferromagnetically ordered FCC Fe with a latt ice parameter near that of bulk Cu. Nevertheless, the sensitivity of t he multiple-scattering calculations of both the Fe2p and Fe3p simulati ons to local order has been used to show that the overlayer structure posseses some level of imperfection or disorder as well.