Crystal effects in the neutralization of He+ ions in the low energy ion scattering regime
Investigating possible crystal effects in ion scattering from elemental surfaces, measurements of the positive ion fraction P+ are reported for He+ ions scattered from single and polycrystalline Cu surfaces. In the Auger neutralization regime, the ion yield is determined by scattering from the outer...
Saved in:
Published in | Physical review letters Vol. 100; no. 21; p. 213201 |
---|---|
Main Authors | , , , , |
Format | Journal Article |
Language | English |
Published |
United States
30.05.2008
|
Online Access | Get more information |
Cover
Loading…
Summary: | Investigating possible crystal effects in ion scattering from elemental surfaces, measurements of the positive ion fraction P+ are reported for He+ ions scattered from single and polycrystalline Cu surfaces. In the Auger neutralization regime, the ion yield is determined by scattering from the outermost atomic layer. For Cu(110) P+ exceeds that for polycrystalline Cu by up to a factor of 2.5, thus exhibiting a strong crystal effect. It is much less pronounced at higher energies, i.e., in the reionization regime. However, there a completely different angular dependence of the ion yield is observed for poly- and single crystals, due to massive subsurface contributions in nonchanneling directions. |
---|---|
ISSN: | 0031-9007 |
DOI: | 10.1103/PhysRevLett.100.213201 |