▎ 摘　　要

We report Ne atom scattering from clean Ru(0001) and from Ru(0001) covered with a single layer of graphene. For both systems, the quantum and classical regimes are observed and analyzed. The quantum to classical boundary is explored by varying both the surface temperature and the incident Ne kinetic energy. The classical smooth surface model is used to perform theoretical simulations in order to reproduce the angular distributions in the classical regime and determine the effective surface mass and hence allow determination of the Debye temperature. The theoretical calculations, in agreement with experiments, predict angular distributions that are subspecular at low energies and shift to supraspecular with increasing incident energy. The energy-resolved spectra in the classical regime exhibit only a single and somewhat broad multiphonon peak, but this peak persists into the regime where quantum features are also observed; thus care must be taken to avoid misinterpretation of the multiphonon background peak as a single phonon feature.