Abstract

Neutralization of light 4He+ ions in backscattering geometry is studied on a single crystalline Cu(1 0 0) and on a poly crystalline Cu-poly surfaces by means of direct comparison of the ion yields. Below 2 keV neutralization is only restricted to the Auger transition involving two electrons. Measurements in this regime revealed a ∼35% higher ion fraction for the single crystal Cu(1 0 0) with respect to the Cu-poly. The observed difference in the neutralization probability is ascribed to a different extension of the electron jellium edge, resulting from different atomic arrangement. © 2007 Elsevier B.V. All rights reserved.