Spin-Polarized Electrons in Collisions of Multicharged Nitrogen Ions with a Magnetized Fe(001) Surface

Abstract

We report on the first spin-resolved energy spectra for the emission of electrons during grazing scattering of 150 keV multicharged nitrogen ions from a magnetized Fe(001) surface. A substantial spin polarization for KLL Auger electrons emitted in the final stage of the neutralization sequence during the interaction of multicharged ions with a metal surface is observed. We conclude from our data that the projectile L shell is dominantly populated by electrons from the conduction band of the target. For low energy electrons we find an increase of their spin polarization with an increase of the projectile charge.

Local Spin Polarization at Surfaces Probed by Hollow Atoms

“…3 follow a temperature evolution similar to the one for He 2 ions, i.e., a decrease of the higher spin states with increasing temperature and no changes above T C . This implies that the electrons originally stem from the conduction band in line with the results of spin analysis of high-energy (KLL region) electrons emitted from fast, grazing incidence N 6 ions on a magnetized Fe(001) surface [12]. A quantitative analysis of the FIG.…”

“…The temporal state population is determined by an intricate interplay of electron capture and reionization [7]. In the neutralization processes the spin polarization of the captured electrons is conserved [12,13]. Therefore, the probability of ions capturing electrons into specific spin states depends on the respective densities of majority and minority electrons near the Fermi level.…”

Collisions of Slow Highly Charged Ions With Surfaces

“…Electrons from the conduction band are, in general, spin polarized while core states giving rise to "side feeding" [9] show little to no polarization. Comparison of a recent COB simulation [68] with the polarization data [66] shows reasonably good agreement for energetic electrons originating from KLL Auger transitions in N 6+ (Fig. 13).…”

“…Optical polarization measurements of excited states provide a complementary route [65]. Very recently, the investigation of 2D magnetism has been extended to multiply charged ions [66,67]. Spinpolarized electron emission by N 6+ scattered at a Fe (001) surface has been used as a "label" for the electrons involved in the hollow atom formation.…”