Tribological Characterization of Nanoclustered Lead Films

For thin films of Pb on Ti, a system which does not wet, it is known that when studying coverages below the percolation transition measurement of surface friction via a sliding gas monolayer is an effective probe of electronic structure for the isolated lead nanoclusters.\footnote{Highland, M.\ et al.\, in preparation.} This technique is capable of studying superconductors as they pass through the transition temperature. Motivated by on-going reports of quantum size effects in thin lead films grown on Si(111)\footnote{Ozer, M.\ et al.\ {\it J.\ Low Temp Phys.} {\bf 2009}, 157: 221-251.} and Cu(001),\footnote{Li, W.\ et al.\ {\it Phys.Rev.B} {\bf 1993}, 48, 11: 8336-8344.} we examine the issue of nitrogen adsorption\footnote{Krim, J.and Widom, A.\ {\it Phys.\ Rev.\ B} {\bf 1988}, 38: 12184-12189.} onto such nanostructured films. Funding provided by NSF DMR.