Theory of noncontact dissipation force microscopy

Abstract

The interaction between the tip of the noncontact atomic force microscope (nc-AFM) and a surface is analyzed using the Langevin equation approach. The existence of an intrinsically local energy dissipation mechanism is demonstrated. This mechanism fundamentally differs from that related to adhesion hysteresis between the tip and the surface. A scheme referred to as noncontact dissipation force microscopy is proposed for producing surface images in ultrahigh vacuum. Moreover, a prospect for scanning probe microscopy is raised, namely, the possibility of measuring nanomechanical surface properties. It is also shown how nc-AFM operated at large amplitude could be used in principle to measure profiles of both the tip-surface interaction force and its gradient.