Reciprocity in quantum reflection of atoms from a diffraction grating

Abstract

We report on an experimental test of the reciprocity principle in quantum reflection of helium atoms from a diffraction grating. Helium atom beams are reflected from a blazed grating at grazing incidence angles of a few mrad. At these conditions the atoms are quantum reflected tens of nanometer above the surface. The reciprocity principle is found to hold even at Rayleigh conditions where the emergence of a new diffraction beam causes abrupt variations of the diffraction efficiencies. The reciprocity principle allows us to predict diffraction efficiencies for configurations which cannot be implemented in the experiment.