title: Quasi-resonant neutralization of He+ ions at a germanium surface.
abstract: When low-energy He ions are scattered from a Ge surface, the fraction of positive ions exhibits characteristic oscillations as a function of ion energy. These oscillations are caused by quasi-resonant neutralization (qRN), a process which is active for materials with a narrow band nearly resonant with the unperturbed He 1s-level. In this paper we measure the fraction of He+ backscattered from Ge(100). In conjunction with recently developed theoretical methods, we extract quantitative information on the efficiency of qRN. Our evaluation reveals that qRN is a highly efficient process leading to ion fractions two orders of magnitude lower than in systems for which neutralization is only due to Auger processes.
authors.forename: D
authors.initials: D
authors.lastname: Goebl
authors.forename: D
authors.initials: D
authors.lastname: Roth
authors.forename: D
authors.initials: D
authors.lastname: Primetzhofer
authors.forename: R C
authors.initials: RC
authors.lastname: Monreal
authors.forename: E
authors.initials: E
authors.lastname: Abad
authors.forename: A
authors.initials: A
authors.lastname: Putz
authors.forename: P
authors.initials: P
authors.lastname: Bauer
mesh_terms: D004583:Electrons; D005857:Germanium / Q000737:chemistry*; D006371:Helium / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D005857:Germanium; D006371:Helium