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arXiv · 1307.3153

Quasi-resonant neutralization of He+ ions at a germanium surface

D. Goebl·D. Roth·D. Primetzhofer·R. C. Monreal·E. Abad·A. Putz·P. Bauer
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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 can be observed for materials with a narrow band nearly resonant with the unperturbed He-1s level. In the present manuscript, we employ recently developed theoretical methods to 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.

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D. Goebl, D. Roth, D. Primetzhofer, R. C. Monreal, E. Abad, A. Putz, P. Bauer. 2013-11-22. Quasi-resonant neutralization of He+ ions at a germanium surface. https://doi.org/10.1088/0953-8984%2F25%2F48%2F485006

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