Frictional Van der Waals force on a neutral AFM probe moving near a flat dielectric surface
In this article we present an expression for the frictional Van der Waals force, obtained within an additivity approximation, on a neutral AFM probe moving near a flat dielectric surface. As a basic point, we used an expression for the force interaction between two small neutral particles, obtained within a theory of nonretarded fluctuating electromagnetic interaction. The geometry of probe is appropriated as a sectioned cone with spherical apex. The numerical calculations were carried out using the Debye dielectric function for the particle and sample materials depending on the frequency. We take into consideration the thin film of water, which is condensed on sample surface on air. As a result, after analyzing numerical calculation data, we can conclude that the frictional forces can be measured in atomic force microscopy experiments on dielectric materials.