Surface-plasmon mediated proton neutralization at metal surfaces

Abstract

Proton neutralization at gold surfaces by surface-plasmon emission is analyzed. Transition rates and neutralization fractions are evaluated within the fixed-ion approximation and compared with those for the usual Auger channel. We found that for protonsurface distances larger than one bohr radius the collective transition rates are larger than the Auger rates, while the neutralization fractions are very similar for both channels. Therefore in those situations in which the collective mode is energetically allowed, which is the case for several metals, it has to be considered simultaneously with the Auger and resonance tunneling modes.