He-diamond interaction probed by atom beam scattering

Abstract

A ${}_{}{}^4{}_{}{}^{}\mathrm{He}$ atomic beam was used to probe the He-C (diamond) interaction. Selective adsorption features have been measured and three energy levels identified: 6.4, 3.0, and 1.1 meV with a standard deviation of 0.1 meV. Diffraction patterns showed weak diffraction up to the second order; a corrugation parameter of 0.021 Å was obtained with the use of a hard-wall model in the eikonal approximation. An extensive study of surface preparation was carried out and the results of ${}_{}{}^4{}_{}{}^{}\mathrm{He}$ diffraction for different methods of surface cleaning are reported.