Frequency shift, damping, and tunneling current coupling with quartz tuning forks in noncontact atomic force microscopy

Laurent Nony (1) , Franck Bocquet (1) , Franck Para (1) , Christian Loppacher (1)

1 IM2NP - Institut des Matériaux, de Microélectronique et des Nanosciences de Provence

A combined experimental and theoretical approach to the coupling between frequency-shift (∆f), damping and tunneling current (It) in combined non-contact atomic force microscopy/scanning tunneling microscopy using quartz tuning forks (QTF)-based probes is reported. When brought into oscillating tunneling conditions, the tip located at the QTF prong's end radiates an electromagnetic field which couples to the QTF prong motion via its piezoelectric tensor and loads its electrodes by induction. Our approach explains how those It-related effects ultimately modify the ∆f and the damping measurements. This new paradigm to the origin of the coupling between It and the nc-AFM regular signals relies on both, the intrinsic piezoelectric nature of the quartz constituting the QTF and its electrodes design.

Mots clés: non-contact Atomic Force Microscopy; Scanning Tunneling Microscopy; quartz tuning fork; frequency shift; tunneling current; piezoelectricity; electromagnetic coupling

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

Laurent Nony, Franck Bocquet, Franck Para, Christian Loppacher. Frequency shift, damping, and tunneling current coupling with quartz tuning forks in noncontact atomic force microscopy. Physical Review B: Condensed Matter and Materials Physics (1998-2015), 2016, 94 (115421), ⟨10.1103/PhysRevB.94.115421⟩. ⟨hal-01519661⟩