MAGNETIC CIRCULAR-DICHROISM IN PHOTOEMISSION FROM RARE-EARTH MATERIALS - A NEW TECHNIQUE IN SURFACE AND THIN-FILM MAGNETISM

Using circularly polarized x rays to excite photoelectrons from magnet ically ordered rare-earth materials gives rise to large magnetic circu lar dichroism in photoemission (MCD-PE). l. e. the intensity of 4f-pho toemission lines strongly depends on the orientation of sample magneti zation with respect to the photon spin. To explore its potential for a pplication as near-surface magnetometer with atomic-layer resolution, we studied MCD-PE at the (0001)-surfaces of Gd and Tb where the magnet ization of the topmost atomic layer - by help of the surface core-leve l shift - is specroscopically separated from the bulk magnetization. I n thin films containing different rare earths MCD-PE allows to monitor the magnetization in an element specific way. This is demonstrated us ing the ordered heteromagnetic interface Eu/Gd as an example.