Optomechanical atomic force microscope.

In the scanning probe microscope system, the weak signal detection of cantilever vibration is one of the important factors affecting the sensor sensitivity. In our current work, we present a novel design concept for an atomic force microscope (AFM) combined with optomechanics with an ultra-high quality factor and a low thermal noise. The detection system consists of a fixed mirror placed on the cantilever of the AFM and pump-probe beams that is equivalent to a Fabry-Perot cavity. We realize that the AFM combined with an optical cavity can achieve ultra-sensitive detection of force gradients of 10 N m in the case of high-vacuum and low effective temperature of 1 mK, which may open up new avenues for super-high resolution imaging and super-high precision force spectroscopy.