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arXiv · 1005.3711

Coherent reflection of He atom beams from rough surfaces at near-grazing incidence

Bum Suk Zhao·H. Christian Schewe·Gerard Meijer·Wieland Schöllkopf
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Abstract

We here report coherent reflection of thermal He atom beams from various microscopically rough surfaces at grazing incidence. For a sufficiently small normal component $k_z$ of the incident wave-vector of the atom the reflection probability is found to be a function of $k_z$ only. This behavior is explained by quantum-reflection at the attractive branch of the Casimir-van der Waals interaction potential. For larger values of $k_z$ the overall reflection probability decreases rapidly and is found to also depend on the parallel component $k_x$ of the wave-vector. The material specific $k_x$ dependence for this classical reflection at the repulsive branch of the potential is explained qualitatively in terms of the averaging-out of the surface roughness under grazing incidence conditions.

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Bum Suk Zhao, H. Christian Schewe, Gerard Meijer, Wieland Schöllkopf. 2010-05-20. Coherent reflection of He atom beams from rough surfaces at near-grazing incidence. https://doi.org/10.1103/physrevlett.105.133203

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