Scattering of He Atoms from a Microstructured Grating: Quantum Reflection Probabilities and Diffraction Patterns

• Published in: The journal of physical chemistry letters 2017-03, Vol.8 (5), p.1009-1013
• Main Authors: Miret-Artés, Salvador, Pollak, Eli
• Format: Article
• Language: English
• ISSN: 1948-7185; 1948-7185
• DOI: 10.1021/acs.jpclett.6b02991

The quantum reflection measured previously by Zhao et al. ( Phys. Rev. A 2008, 78, 010902­(R) ) for the scattering of He atoms off of a microstructured grating is described and analyzed theoretically. Using the close-coupling formalism with a complex absorbing potential and describing the long-range interaction in terms of the Casimir–van der Waals potential, we find probabilities and diffraction patterns that are in fairly good agreement with the experimental results. The central outcomes of this study are two-fold. First is the theoretical confirmation that, indeed, the phenomenon of quantum reflection may be detected not only through the elastic peak but also in terms of a quantum reflected diffraction pattern. Second, we demonstrate that the phenomenon of quantum reflection is the result of a coherent process where all of the potential regions are involved on an equal footing. It is a nonlocal property and cannot be related only to the long-range badlands region of the potential of interaction.