| Texto completo | |
| Autor(es): |
Granato‚ E.
;
Ying‚ SC
Número total de Autores: 2
|
| Tipo de documento: | Artigo Científico |
| Fonte: | TRIBOLOGY LETTERS; v. 39, n. 3, p. 229-233, 2010. |
| Resumo | |
We study the velocity dependence of the frictional force of the tip of an atomic force microscope as it is dragged across a surface, taking into account memory effects and thermal fluctuations. Memory effects are described by a coupling of the tip to low frequency excitation modes of the surface in addition to the coupling to the periodic corrugation potential. We find that when the excitation mode frequency is comparable to the characteristic frequency corresponding to the motion of the tip across the surface, the velocity dependence of the frictional force is non-monotonic, displaying a velocity range where the frictional force can decrease with increasing velocity. These results provide theoretical support for the interpretation of recent experiments which find a frictional force that decreases with velocity on surfaces covered with a monolayer. (AU) | |
| Processo FAPESP: | 07/08492-9 - Dinâmica, defeitos topológicos e transições de fase em meios ordenados |
| Beneficiário: | Enzo Granato |
| Modalidade de apoio: | Auxílio à Pesquisa - Temático |
| Processo FAPESP: | 09/01942-4 - See Chen Ying | Brown University - Estados Unidos |
| Beneficiário: | Enzo Granato |
| Modalidade de apoio: | Auxílio à Pesquisa - Pesquisador Visitante - Internacional |