DOMINANCE OF PHONON FRICTION FOR A XENON FILM AN A SILVER(111) SURFACE

Molecular dynamic simulations for a Xe film sliding on an Ag(111) subs trate are performed from the submonolayer through the bilayer regime, which, when compared to both friction and surface resistivity measurem ents, demonstrate that the friction in this system is dominated by pho non excitations. Slip times are found both by direct calculation of th e decay of the center-of-mass velocity, as well as from the decay of t he velocity correlation function, Agreement of the slip times from the two methods supports the occurrence of a friction force Linear in vel ocity over a wide velocity range.