Image potential and local field effects on ionization rates in the field ion microscope

Abstract

Effects of blh the local field and the image potential are taken into account in the determination of the ionization mer of the imaging gas in the Eeld ion miaompe. The model consists of a half-sphere superimposed on a Rat surface and the mults were obtained after the ~WKB scheme. In comparison with the more usual mdses, where only the external 6eld and the atom potential are considered, the wmll eEeR is to Marrow the ionization wne and Io decrease the ionimtion rate, except for the pan of the ionization zone closer1 10 Ihe surface.