Abstract
A cold beam of atoms is used at grazing incidence to study the quantum reflection on a flat polished silicon surface. We measure the reflectivity as a function of the normal incident velocity component between 3 and . Our result is in reasonable agreement with a calculation of the attractive van der Waals surface potential using the dielectric function of Si and the dipole polarizability of . We discuss the influence of the conductivity and of a thin oxide layer on the potential. By comparing our data to those previously measured with atoms, we are also able to confirm the scaling of the reflectivity with atomic mass.
- Received 4 January 2005
DOI:https://doi.org/10.1103/PhysRevA.71.052901
©2005 American Physical Society