Mixed-mode oscillations of an atomic force microscope in tapping mode

Area of Science:

• Physics
• Materials Science
• Nanotechnology

Background:

• Tapping mode atomic force microscopy (TM-AFM) is crucial for high-resolution surface imaging.
• Mixed-mode oscillations in TM-AFM probes can cause anomalous jitter, degrading image accuracy.
• Understanding these oscillations is vital for improving measurement precision.

Purpose of the Study:

• To investigate the formation mechanisms of mixed-mode oscillations in TM-AFM under low-frequency resonant excitation.
• To analyze the different types and patterns of mixed-mode oscillations observed.
• To provide insights for mitigating detrimental oscillations and enhancing TM-AFM performance.

Main Methods:

• Analysis of bifurcation sets for the fast subsystem.
• Investigation of phase trajectory transition patterns (two-jump and four-jump).
• Application of basin of attraction and fast-slow analysis.

Main Results:

• Identified typical two coexisting branches and novel three coexisting branches of equilibrium point attractors.
• Characterized distinct transition patterns in stable and bi-stable cases, including jumps between quiescent and spiking states.
• Unfolded the dynamic mechanisms behind mixed-mode oscillations with varied switching patterns.

Conclusions:

• The study deepens the understanding of complex mixed-mode oscillations in TM-AFM.
• Findings offer valuable insights for improving image quality and measurement precision.
• Mitigation strategies for detrimental oscillations can be developed based on this research.