Investigation of thermal energy atomic scattering from solid surfaces using the 3D time-dependent Schrödinger equation

Abstract

The thermal energy atomic scattering from solid surfaces is very useful tool in the energy range of 10–100meV because the usually applied He probe particles do not penetrate into the surface but provide information about the top layer. We focused on the scattering from ideally periodic and disordered surfaces. The physical model contains an appropriate 3D interaction potential and a 3D Gaussian wave-packet. The interaction potential describes the periodicity or the disorder of the surfaces. The Gaussian wave-packet characterises the atomic beam as an ensemble of independent particles with finite energy spread. The propagation of the Gaussian initial wave function has been determined by the solution of the 3D time-dependent Schrödinger equation. The probability density function has been rendered at the detector region in real space and in momentum space. The slices of the probability density function parallel to the surface provide the surface topography not only in the case of an ideally periodic surface structure but also in the case of disorder.