Simulation of Oscillatory Scattered Ion Yields in He+-Metal Surface Scattering Including the Coulomb Repulsive Interaction

摘要

The effect of the intra-atomic Coulomb repulsive interaction, U, between different electrons in He atoms on the ion survival probability (ISP) is calculated with the mean-field (Hartree-Fock) approximation when He+ is scattered from metals, such as Ga, In, Sn, and Pb. The results suggest that the period of the ISP oscillation is insensitive to U, with U interfering with only the resonant neutralization. The period is determined by the interaction between ions and the surface; a strong interaction shortens the period. In addition, ions are easily neutralized when bandwidth D is large. Furthermore, we simulate the scattered ion yield, assuming that U depends on the ion-metal distance because screening caused by the electron transfer increases as the distance decreases. The simulated scattered ion yield explains the observed yield qualitatively, implying that the screening of U plays an important role in the neutralization process.