Stability analysis of an oscillating tip-cantilever system in NC-AFM

Gérard Couturier (1) , Laurent Nony (2) , Rodolphe Boisgard (1) , Jean-Pierre Aimé (1)

1 CPMOH - Centre de physique moléculaire optique et hertzienne
2 L2MP - Laboratoire matériaux et microélectronique de Provence

This paper is a theoretical and a numerical investigation of the stability of a tip-cantilever system used in noncontact atomic force microscopy (NC-AFM) when it oscillates close to a surface. No additional dissipative force is considered. The theoretical approach is based on a variational method exploiting a coarse grained operation that gives the temporal dependance of the non-linear coupled equations of motion in amplitude and phase of the oscillator. Stability criterions for the resonance peak are deduced and predict a stable behavior of the oscillator in the vicinity of the resonance. The numerical approach is based on the results obtained with a virtual NC-AFM developed by our group. The effect of the size of the stable domain in phase is investigated. These results are in particularly good agreement with the theoretical predictions. Also they show the influence of the phae shifter in the feedback loop and the way it can affect the damping signal.

Mots clés: Non-linear dynamics; Dynamic force microscopy; Stability analysis

Domaines: Agrégats Moléculaires et Atomiques [physics.atm-clus]

Gérard Couturier, Laurent Nony, Rodolphe Boisgard, Jean-Pierre Aimé. Stability analysis of an oscillating tip-cantilever system in NC-AFM. Applied Surface Science, 2002, 188, pp.341-348. ⟨hal-00012047⟩