Energy dissipation in dynamic force microscopy on KBr(001) correlated with atomic-scale adhesion phenomena

Abstract

Atomic-scale adhesion phenomena between KBr tip and sample were studied by dynamic force spectroscopy with a small amplitude of down to 285 pm at room temperature. The high-resonance frequency of the second flexural mode of a silicon cantilever (≈1 MHz) suppresses an apparent dissipation energy caused by undesirable mechanical couplings in between the cantilever and the dither piezo actuator. Further, the Joule heating dissipation contribution and the noise-equivalent dissipation energy were reduced by setting a smaller amplitude. Usage of a high resonance frequency and a smaller amplitude enables us to perform highly sensitive measurements of the atomic-scale adhesion and the tip-instability-related energy dissipation. Tip changes, caused by tip-sample interactions and thermal energy, resulted in three different dissipation energy levels ( E ts ≈ 25 meV/cycle). This infrequent change of the tip apex condition often prevents a stable imaging with small amplitude. Our systematic measurement shows that the atomic adhesion is caused mainly in the tip itself, and a sharper and softer tip induced a larger energy dissipation.

Energy Loss Triggered by Atomic-Scale Lateral Force

“…4S in the Supplemental Material [40] for more details); the atomic contrast in E Z map is weak but anyway visible on top of the large offset. This behavior is consistent with the mechanical coupling issue [46,47].…”

Morphology Change of C60 Islands on Organic Crystals Observed by Atomic Force Microscopy

“…51,52 The values for A exc were extracted from the dissipation images obtained experimentally. In order to do so, we first identified, in the topographic images, the areas where we noticed a clear modification of the island morphology (which is characterized by curved edges for instance).…”

Coupled molecular and cantilever dynamics model for frequency-modulated atomic force microscopy

“…First the Lennard-Jones potential serves as a reference case. Then, a Coulomb interaction is added in order to simulate KBr, which has been studied extensively in experiments [ 24 , 27 – 28 ].…”