Positron Surface States on Clean and Oxidized Al and in Surface Vacancies

24 January 1983

journal article
research article
Published by American Physical Society (APS) in Physical Review Letters

Vol. 50 (4) , 281-284
https://doi.org/10.1103/physrevlett.50.281

Abstract

This Letter reports on the first discrete-lattice calculation of positron surface states on the surfaces of Al. The authors reproduce the observed values and anisotropy of the binding energies on clean surfaces, and predict the surface-state lifetimes. The temperature-independent lateral diffusion constant is calculated. Monovacancies on surfaces are predicted not to trap positrons. The effect of ordered chemisorbed monolayers of oxygen is investigated: Oxidation makes the surface state unstable with respect to positronium emission.

Keywords

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