Active damping by Q-control for fast force-distance curve measurements in atomic force microscopy.

This paper investigates the benefit of active damping by an analog Q-control circuit for measuring fast force-distance curves in atomic force microscopy. By active damping of the cantilever oscillation after snap-off, the down-ring time-constant is reduced significantly from 385 μs to 23 μs. Experimental results demonstrate that the number of force-distance curves per second can be increased by a factor of more than 30.