The nature of the long range forces in atomic force microscopy (AFM) between a tungsten tip and the Au(111) surface is studied within Quantum Nano Dynamics (QND), treating many‐particle interactions and long range screening effects. A new mechanism of long range forces between a neutral tip and a metal surface is suggested due to the interaction with the image potential in the tip and the sample of a single electron localized on the Au(111) surface in front of the tip, in the presence of the AFM tip, and the image screening it provides.
Force between a W‐tip and Au(111) – measured in AFM (circles and crosses, left‐hand axis, Ref. [1]) and calcu‐lated within QND theory (full curve, right‐hand axis).
(© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)