Modeling Energy Dissipation in Atomic Force Microscopy

Atomic force microscopy is an important research tool in micro- and nano-scale science because of its high resolution and versatility. Many different operation methods have been developed and more are being developed. In numerical studies, a nonlinear interaction force model is recognized as a necessary part to achieve accurate results. However, the energy dissipation in the system is still generally modeled only by structural and viscous damping which are proportional to velocity, and the non-conservative interaction force models for numerical simulations are limited and frequently not used. In this work, the authors investigate the importance of using a non-conservative interaction force model in numerical simulations. Some modeling methods are discussed and the simulation results for resonant excitation are compared. The response magnitude at the first harmonic is determined to be significantly affected by the modeling approach when the dissipative level in the tip-sample interaction and the structural and viscous damping are high.