NIST logo

Publication Citation: Spin Polarized Metastable Atom He De-excitation, Theory

NIST Authors in Bold

Author(s): David R. Penn; S Apell;
Title: Spin Polarized Metastable Atom He De-excitation, Theory
Published: January 01, 1991
Abstract: Metastable spin-polarized He* atoms incident on a Ni surface undergo deexcitation in a process which yields electron from the Ni. The number produced is observed to depend on the relative spin of teh Ni and the He* atoms. The normalized difference in the ejected-electron intensity producted by He* atoms with opposite spin polarizations increases dramatically with increasing kinetic energy of the electrons. A theory of this asymmetry is presented. It is found that the experimental results can be reproduced only by the use of a realistic potential for the Ni electrons in the vacuum region. With such a potential, it is found Potential, is is found that He+ ions which result from the He*-surface interaction are neutralized at ~4.5 {Aring} from the Ni surface, a much larger distance than given by previous estimates. The experiment is shown to reflect the polarization of Ni electrons at the He ion, and it is estimated that the Ni magnetization at the Fermi energy and far from the Ni surface is -20%.
Citation: Revista Colombiana de Fisica
Volume: 24
Issue: 2
Research Areas: Surface Physics