Thermal effects on atomic friction

We model friction acting on the tip of an atomic force microscope as it is dragged across a surface at non-zero temperatures. We find that stick-slip motion occurs and that the average frictional force follows $|\ln v|^{2/3}$, where $v$ is the tip velocity. This compares well to recent experimental work (Gnecco et al, PRL 84, 1172), permitting the quantitative extraction of all microscopic parameters. We calculate the scaled form of the average frictional force's dependence on both temperature and tip speed as well as the form of the friction-force distribution function.Comment: Accepted for publication, Physical Review Letter

AFM Imaging in Physiological Environment: From Biomolecules to Living Cells

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Grafting processes studied with a nanotip: Silane molecules and polymers grafted on silica and silanized silica surfaces

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Grafting processes studied with a nanotip: Silane molecules and polymers grafted on silica and silanized silica surfaces

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Préparation de structures périodiques de polyacétylène substitué par microscopie à force atomique en mode contact : compétition entre friction et pelage

Dans ce papier, nous présentons une tentative de modification de la surface d'un film de polyacétylène déposé sur du mica. L'étude est réalisée à l'aide d'un M.F.A. en mode contact. Nous montrons l'influence de la vitesse de balayage de la pointe et de la force d'application sur l'amplitude de la période des fagots formés lors du balayage

Structuration et nanorhéologie d’un liquide confiné: étude par AFM dynamique.

In this paper, we present two types of experimental results. Firstly presented are very good results recently obtained within our group (Nanophysics on soft material and biological systems-CPMOH-Université Bordeaux 1) at the end of a study carried out on octamethylcyclotetrasiloxane (C8H26Si4O3) confined between a plane solid graphite surface and the tip of a commercial Atomic Force Microscope (AFM), used in dynamic mode tapping. Secondly more recent results of a study undertaken on the confinement of salted water, by the same technique, on the mica plane surface are analysed. We show that when the AFM tip approaches the surface, the variation of the amplitude and of the delay of phase of the detected signal, according to the tipsurface distance, present oscillations. The measurement of the period of these oscillations provides a value equal to the diameter of the molecule of the confined liquid