Cantilever dynamics in amplitude modulation AFM: continuous and discontinuous transitions

Sergio Santos (1) , Victor Barcons (2) , Josep Font (2) , Neil H Thomson (1)

1 School of Physics and Astronomy & Astbury Centre for Structural Molecular Biology
2 Departament d'Enginyeria Electrònica [Barcelona]

Transitions between the attractive and the repulsive force regimes for amplitude modulation AFM can be either dis-continuous, with a corresponding jump in amplitude and phase, or continuous and smooth. During the transitions, peak repulsive and average forces can be up to an order of magnitude higher when these are discrete. Under certain circumstances, for example when the tip radius is relatively large (e.g. R>20-30nm), and for high cantilever free amplitudes (e.g. A>40-50nm), the L-state can be reached with relatively low set-points only (e.g. A sp / A 0 <0.30). We find that these cases do not generally lead to higher resolution despite the fact that the imaging can be non-contact.

Mots clés: Physical Sciences

Sergio Santos, Victor Barcons, Josep Font, Neil H Thomson. Cantilever dynamics in amplitude modulation AFM: continuous and discontinuous transitions. Journal of Physics D: Applied Physics, 2010, 43 (27), pp.275401. ⟨10.1088/0022-3727/43/27/275401⟩. ⟨hal-00569645⟩