Atomic electron energy spectra of slow He2+ ions impinging on metallic surfaces

Changes in the KLL Auger electron spectra of slow He2+ ions impinging on surfaces have been proposed as diagnostics of local spin polarization at ferromagnetic surfaces. For a variety of targets Gd(0 0 0 1), Ni(1 1 0), Fe(1 1 0) and Al(1 1 0) and different ion energies (20–1000 eV) and angles of incidence (5–75°) the KLL spectra have been studied. The line ratios depend on the scattering conditions and on the target used, which may give access to the exact behavior of the electronic states in the vicinity of the surface. Additional information on the ion neutralization processes may be available from the angular distributions of the emitted electrons.