Amorphous GdCo: Effect of surface segregation on reading of the magnetization by spin-polarized photoemission

Abstract

Spin-polarized photoemission can be used to read the surface magnetization direction of perpendicularly magnetized amorphous GdCo films. Effects specific of the photoemission process are observed: (1) surface depolarization by disordered Gd moments in the outermost segregated layers of the film, (2) change of the polarization upon varying the probing depth of the photoelectrons. Both effects are consequences of the inhomogeneous surface composition of amorphous GdCo due to segregation.