Dispersion curves of dry (black full lines) and wet samples probed down to 150 µm depth (dotted lines) in α-Al2O3 in the
Gamma-Z direction.
M. Warburton, J.M. Ablett, J.-P. Rueff, P. Baroni, L. Paolasini, L. Noirez
We examine the influence at room temperature of the deposit of a water layer on the phonon dynamics of a solid. It is shown that the water wetting at the surface of an Alumina monocrystal has deep effects on acoustic phonons, propagating over several hundred µm distance and taking place on a relatively long time scale. The effect of the wetting at the boundary is two-fold: a hardening of both transverse and longitudinal acoustic phonons is observed as well as a relaxation of internal stresses. These acoustic phonon energy changes were observed by inelastic X-ray scattering up to 40 meV energy loss, allowing us to probe the solid at different depths from the surface.
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Physics, chemistry, nanoscience and materials around large instruments Physique, chimie, nanosciences et matériaux autour des grands instruments
• Laboratoire Léon Brillouin (LLB) • Leon Brillouin Laboratory (LLB)
• Nouvelles frontières dans les matériaux quantiques - NFMQ
• Diffraction • Diffraction de rayons X • Rayonnement synchrotron • Rayons X
