Abstract :
[en] Diffraction of fast helium atoms at alkali-halide surfaces under grazing angles of incidence shows intriguing diffraction patterns. The persistence of quantum coherence is remarkably strong, even though high surface temperatures and high (keV) kinetic energies of the incident atoms would strongly suggest the dominance of dissipative and decohering processes. The main source of decoherence is the excitation or absorption of surface vibrations upon impact. The momentum transfer between the surface and the incident helium atom depends on the amplitude of the thermal vibrations of the surface atoms and the energy of the incident particle. We present an ab initio simulation of the quantum diffraction of fast helium beams at a LiF (100) surface in the < 110 > direction, and compare with recent experimental diffraction data.
Aigner, F.; Vienna University of Technology > Institute for Theoretical Physics
Simonovic, N.; Institute for Theoretical Physics, Vienna University of Technology / Institute of Physics, Belgrade
Solleder, B.; Vienna University of Technology > Institute for Theoretical Physics
Burgdörfer, Joachim; Vienna University of Technology > Institute for Theoretical Physics
Commentary :
AUG 25-29, 2008
24th Summer School and International Symposium on Physics of Ionized Gases
Novi Sad
SERBIA
Malovic, G Popovic, L Dimitrijevic, M
Scopus citations®
without self-citations
4