Thickness-dependent nanofriction of a rare gas monolayer sliding on Pb(111) ultrathin films

• Published in: Europhysics letters Vol. 113; no. 4; p. 46002
• Main Authors: Cai, X. L., Wang, J. J., Fu, X. N., Bai, S. Y., Niu, C. Y., Jia, Y.
• Format: Journal Article
• Language: English
• Published: Les Ulis EDP Sciences, IOP Publishing and Società Italiana di Fisica 01.02.2016; IOP Publishing
• Subjects: 68.35.Af; 68.37.-d; Density functional theory; Edge effect; Electronics; First principles; Friction; Modulation; Monolayers; Nanostructure; Oscillations; Rare gases; Size effects; Sliding; Substrates; Thickness; Thin films
• ISSN: 0295-5075; 1286-4854
• DOI: 10.1209/0295-5075/113/46002

The friction can be affected dramatically by quantum size effects (QSEs) and edge effects at nanoscale. The modulations of QSEs on nanofriction of a rare gas (RG) monolayer sliding on Pb(111) ultrathin films were investigated by using the first-principles approach within density functional theory (DFT) with van der Waals (vdW) interaction correction. Our findings revealed that there exist even-odd oscillations in the friction with the thickness of Pb(111) substrate and the friction can be tuned up to 30% by the different thicknesses of Pb(111) films. Moreover, such modulation is more obvious for the RG adatoms with larger radius. The underlying physics is that the oscillations of the electronic density of states at Fermi level induce different interactions and energy barriers between RG and Pb(111) films with different thicknesses. Overall, we here propose an approach to tune friction and a way to identify the electronic contribution to friction via the different thicknesses of substrates at nanoscale.