Quantum-size effects in thin solid xenon films

• Published in: Journal of electron spectroscopy and related phenomena 1999-01, Vol.98-99, p.121-131
• Main Authors: Grüne, M, Pelzer, T, Wandelt, K, Steinberger, I.T
• Format: Article
• Language: English
• Subjects: Insulating films; Quantum size effects; Ultraviolet; Ultraviolet photoelectron spectroscopy; Xenon
• ISSN: 0368-2048; 1873-2526
• DOI: 10.1016/S0368-2048(98)00281-3

Ultraviolet photoelectron spectra of solid xenon films on top of Ru(0001) and Cu(100) substrates revealed peak patterns due to confinement of electrons in quantum wells formed by the metal substrate–Xe insulator–vacuum system. The data (along with previous ones for Pt(100) substrates) were analyzed, assuming simple tight-binding dispersion in the direction ΓΛ, perpendicular to the film, expressly taking into account the polarization of the first monolayer adjacent to the metal. The good fit obtained implied that the sets of experiments sampled the 5p3/2mj=1/2 and 5p1/2 valence bands at several points of the actual dispersion curves, furnishing an experimental determination of these curves along the ΓΛ direction. The absolute value of the effective mass μ∗ for the electrons at the top of the bands (in terms of the free electron mass) was found to be near unity for both bands, depending somewhat on the substrate. These substrate-dependent variations are attributed to the effect of the substrate on the potential and the wave function in the Xe films, combined with imperfections in the texture and structure of the films.