Field Adsorption of Inert-Gas Atoms on Field Ion Emitter Surfaces

Abstract
Theories of field ionization assume an atomically clean surface. Atom-probe experiments surprisingly revealed that the inert imaging gases are adsorbed at the field ion emitter. It is shown that this adsorption is due to a short-range field-induced dipole-dipole interaction. Adsorption at the apex of the protruding surface atom has considerable consequences for the mechanism of field ionization and field evaporation.