hide
Free keywords:
-
Abstract:
He atom scattering has been shown to be a sensitive probe of electron−
phonon interaction properties at surfaces. Here it is shown that measurements of the
thermal attenuation of the specular He atom diffraction peak (the Debye−Waller
effect) can determine the electron−phonon coupling constant, λ, for ultrathin films of
metal overlayers on various close-packed metal substrates. Values of λ obtained for
single and multiple monolayers of alkali metals, and for Pb layers on Cu(111),
extrapolated to large thicknesses, agree favorably with known bulk values. This
demonstrates that He atom scattering can measure the electron−phonon coupling
strength as a function of film thickness on a layer-by-layer basis.
