DOUBLE RESONANT NEUTRALIZATION IN HYPERTHERMAL ENERGY ALKALI ION SCATTERING AT CLEAN METAL SURFACES

Abstract: Resonant neutralization of hyperthermal Na+ ions impinging on clean Cu(100) surfaces is studied, focussing on long lived electronic interactions involving the projectile and a target atom. Specific trajectories are considered where the incident particle undergoes multiple collisions within the first surface layers, interacting simultaneously with several target atoms, which leads to single emission of a surface atom that can resonantly exchange charge with both the solid and the projectile. The system is described via a semempirical, one electron potential that includes the effect of a plane metal surface, with projected band gap, the projectile, whose charge state will be eventually investigated, and the substrate atom. On this basis, a model Hamiltonian of the Anderson-Newns type is constructed and the calculated neutralization probability is compared with the angle resolved neutral fraction measured by Keller et al (Phys. Rev. Lett. 75, 1654 (1995

Resonant neutralization of hyperthermal Naþ ions impinging on clean Cuð100Þ surfaces is studied, focussing on long lived electronic interactions involving the projectile and a target atom. Specific trajectories are considered where the incident particle undergoes multiple collisions within the first surface layers, interacting simultaneously with several target atoms, which leads to single emission of a surface atom that can resonantly exchange charge with both the solid and the projectile. The system is described via a semi-empirical, one-electron potential that includes the effect of a plane metal surface, with projected band gap, the projectile, whose charge state will be eventually investigated, and the substrate atom. On this basis, a model Hamiltonian of the Anderson–Newns type is constructed and the calculated neutralization probability is compared with the angle resolved neutral fraction measured by Keller et al. [C.A. Keller, C.A. DiRubio, G.A. Kimmel, B.H. Cooper, Phys. Rev. Lett. 75 (1995) 1654].