J J Paggel | PubMed Health

PubMed2002

Large electron-phonon coupling at an interface.

The strength of electron-phonon coupling in atomically uniform films of Ag on Fe is determined by angle-resolved photoemission from quantum well states in these films over a wide temperature range. As the film thickness is reduced, contributions from the surface and interface should become more important, and, experimentally, a large enhancement with superimposed quantum oscillations is observed. An analysis of the quantum oscillations indicates that this large enhancement is an interface effect.

Journal Article↗

PubMed2001

Quantum electronic stability of atomically uniform films.

We have studied the structural stability of thin silver films with thicknesses of N = 1 to 15 monolayers, deposited on an Fe(100) substrate. Photoemission spectroscopy results show that films of N = 1, 2, and 5 monolayer thicknesses are structurally stable for temperatures above 800 kelvin, whereas films of other thicknesses are unstable and bifurcate into a film with N +/- 1 monolayer thicknesses at temperatures around 400 kelvin. The results are in agreement with theoretical predictions that consider the electronic energy of the quantum well associated with a particular film thickness as a significant contribution to the film stability.

Journal Article↗