By presenting the phase properties of bistability in amplitude-modulation atomic force microscopy, we put forward a technique, the constant-phase mode, which may eliminate bistability. Using this approach, we keep the...By presenting the phase properties of bistability in amplitude-modulation atomic force microscopy, we put forward a technique, the constant-phase mode, which may eliminate bistability. Using this approach, we keep the phase shift between driving and oscillation constant, slightly above -90°. In addition to the adjustment of the free amplitude, we add to amplitude-modulation atomic force microscopy another feedback so that the tip always oscillates in the high-amplitude state. A numerical simulation is carried out to demonstrate that the algorithm prevents bistability effectively.展开更多
基金supported by the National Natural Science Foundation of China (11074019)the National High-Tech Research and Development Program of China (2007AA12Z128)
文摘By presenting the phase properties of bistability in amplitude-modulation atomic force microscopy, we put forward a technique, the constant-phase mode, which may eliminate bistability. Using this approach, we keep the phase shift between driving and oscillation constant, slightly above -90°. In addition to the adjustment of the free amplitude, we add to amplitude-modulation atomic force microscopy another feedback so that the tip always oscillates in the high-amplitude state. A numerical simulation is carried out to demonstrate that the algorithm prevents bistability effectively.